Amazon AWS Certified Developer – Associate DVA-C02 Exam Dumps and Practice Test Questions Set 10 Q181-200

Visit here for our full Amazon AWS Certified Developer – Associate DVA-C02 exam dumps and practice test questions.

Question 181 

A developer is building an event-driven application that must receive events from multiple AWS services and route them to different targets based on filtering rules. Which service should be used?

A) Amazon EventBridge
B) Amazon SNS
C) Amazon SQS
D) AWS Lambda

Answer:  A) Amazon EventBridge

Explanation:

Amazon EventBridge is a serverless event bus that allows developers to route events from AWS services, custom applications, and SaaS providers to multiple targets. It supports advanced filtering rules that can evaluate event content and selectively forward events to specific services. EventBridge also provides schema discovery, making it easier for developers to handle structured event data and integrate with various systems. The service is designed for highly decoupled architectures, allowing components to respond independently to events in near real-time.

Amazon SNS is a fully managed messaging service that enables the publishing of messages to multiple subscribers. While SNS can fan out notifications to SQS queues, Lambda functions, and HTTP endpoints, it does not provide native support for complex rule-based filtering. SNS is better suited for simple pub/sub patterns where messages are broadcasted to all subscribers without content-based routing.

Amazon SQS is a managed message queuing service that decouples components and ensures reliable delivery of messages. SQS is excellent for buffering and asynchronous processing but lacks the ability to filter and route messages to multiple targets based on event content. This makes it unsuitable when applications require conditional routing or complex event handling.

AWS Lambda allows execution of code in response to triggers, including events from EventBridge, SQS, and SNS. However, Lambda itself cannot act as an event router; it is intended for computation rather than message routing. EventBridge is the correct choice because it centralizes event routing, supports filtering, multiple targets, and decouples event producers from consumers, enabling scalable, responsive architectures.

Question 182

A developer needs a fully managed search solution capable of indexing and querying millions of documents with near-real-time updates. Which AWS service is most suitable?

A) Amazon OpenSearch Service
B) Amazon Redshift
C) Amazon S3
D) Amazon RDS

Answer:  A) Amazon OpenSearch Service

Explanation:

Amazon OpenSearch Service is a fully managed solution for search, analytics, and log monitoring. It provides distributed indexing, full-text search, and near-real-time updates, making it ideal for applications that require searching and analyzing millions of documents efficiently. OpenSearch also integrates with visualization tools and supports advanced search features such as aggregations and filtering, which are critical for large-scale search workloads.

Amazon Redshift is a data warehouse service designed for analytics on structured data. It excels at running complex SQL queries on large datasets but is not optimized for full-text search or indexing unstructured documents. While Redshift can analyze large volumes of data, it cannot efficiently serve search queries for textual content in real time.

Amazon S3 is an object storage service for storing files, backups, and unstructured data. While S3 can store massive amounts of data, it does not provide indexing or querying capabilities. Searching S3 objects typically requires integrating with another service, such as OpenSearch or Athena, to perform queries on the stored data.

Amazon RDS is a managed relational database service. It supports structured queries and indexing on relational data but is not designed for handling full-text search at scale. OpenSearch is the correct choice because it is purpose-built for indexing large volumes of data, performing text-based searches, and delivering low-latency results in near-real time.

Question 183 

A developer wants to run containerized applications without managing EC2 instances. Which service should be used?

A) AWS Fargate
B) Amazon EC2
C) Amazon EKS with self-managed nodes
D) AWS Lambda

Answer:  A) AWS Fargate

Explanation:

AWS Fargate is a serverless compute engine for containers that removes the need to provision, scale, or manage servers. Developers simply define container specifications, and Fargate automatically allocates compute resources, handles scaling, and ensures isolation between workloads. This allows teams to focus on application logic rather than infrastructure management.

Amazon EC2 provides virtual servers where containers can run, but it requires developers to manage instances, scaling, and patching. This adds operational overhead and reduces the benefits of serverless architectures when compared to Fargate.

Amazon EKS with self-managed nodes offers a Kubernetes-managed service, but when using self-managed nodes, developers must maintain and scale the worker nodes themselves. While this gives more control, it introduces complexity that Fargate avoids by providing a fully managed compute layer.

AWS Lambda is a serverless function execution service, suitable for short-lived workloads. However, it is not designed for running long-running containerized applications. Fargate is the correct choice because it combines serverless operation with support for full container lifecycles, making it ideal for running microservices and containerized apps without managing infrastructure.

Question 184 

Which service should a developer use to perform canary deployments for Lambda functions?

A) AWS CodeDeploy
B) AWS CodeBuild
C) Amazon ECS
D) AWS CloudFormation

Answer:  A) AWS CodeDeploy

Explanation:

AWS CodeDeploy is a fully managed deployment service that automates application releases and supports advanced deployment strategies such as canary, linear, and blue/green deployments. For Lambda functions, CodeDeploy can gradually shift traffic from an old version to a new version, monitor performance, and automatically roll back if issues are detected. This ensures minimal risk during updates.

AWS CodeBuild is a build service that compiles source code, runs tests, and produces deployable artifacts. It does not handle deployment strategies or manage Lambda traffic shifting. While CodeBuild is essential in CI/CD pipelines, it does not perform canary deployments.

Amazon ECS is a container orchestration service. While ECS supports rolling updates for containerized applications, it is unrelated to deploying Lambda functions. ECS cannot directly manage Lambda traffic or provide Lambda-specific deployment patterns.

AWS CloudFormation is an infrastructure-as-code service that automates provisioning of AWS resources. While CloudFormation can deploy Lambda functions, it does not natively manage incremental deployment strategies such as canaries or traffic shifting. CodeDeploy is the correct choice because it provides safe, automated Lambda deployment capabilities with traffic management and rollback options.

Question 185 

A developer requires durable, low-latency key-value storage for session data. Which service is best?

A) Amazon DynamoDB
B) Amazon RDS
C) Amazon S3
D) Amazon Glacier

Answer:  A) DynamoDB

Explanation:

Amazon DynamoDB is a fully managed NoSQL database designed for key-value and document workloads. It provides microsecond latency at scale, making it ideal for session storage where fast reads and writes are critical. DynamoDB also offers built-in replication, high availability, and automatic scaling, ensuring both durability and performance.

Amazon RDS is a relational database service. While RDS supports transactions and structured data, its latency is generally higher than DynamoDB for small, frequent key-value operations. Maintaining low-latency session storage on RDS can require significant tuning and may not scale as seamlessly.

Amazon S3 is object storage, suitable for storing large files or backups. It does not provide low-latency read/write performance for individual key-value pairs and is not ideal for session data that requires frequent updates and immediate access.

Amazon Glacier is a long-term archival storage service with very high latency for retrieval. It is designed for infrequently accessed data and is unsuitable for session storage. DynamoDB is the correct choice because it provides durable, low-latency access for high-throughput, key-value workloads and can scale automatically to meet application demands.

Question 186 

A developer needs to run SQL queries on JSON data stored in S3 without provisioning servers. Which service should be used?

A) Amazon Athena
B) Amazon Redshift
C) AWS Glue
D) Amazon RDS

Answer:  A) Amazon Athena

Explanation:

Amazon Athena is a serverless query service designed specifically for running SQL queries directly on data stored in Amazon S3. It allows developers to analyze structured, semi-structured, and unstructured data such as JSON, CSV, Parquet, or ORC without the need to manage any infrastructure. Athena scales automatically, charging only for the amount of data scanned, which makes it an efficient and cost-effective solution for ad hoc analysis of large datasets. This eliminates the need for provisioning and managing database servers, making it ideal for developers who want quick insights without operational overhead.

Amazon Redshift, on the other hand, is a fully managed data warehouse that requires the creation of clusters to store and query data. While Redshift supports querying structured data efficiently and can work with external tables in S3 through Redshift Spectrum, it still requires provisioning, sizing, and managing clusters. This setup adds complexity and cost for scenarios where serverless operation and minimal maintenance are priorities. For JSON data that may be infrequently queried, Redshift is less convenient and overkill compared to Athena.

AWS Glue is primarily an ETL (extract, transform, load) service rather than an interactive query engine. Glue can crawl S3 data, catalog it, and transform it into formats suitable for analytics or other processing. However, it is not designed for running ad hoc SQL queries directly on raw JSON files without first preparing the data. While Glue can be integrated with Athena for querying, Glue alone does not meet the requirement for running SQL queries on S3 data serverlessly.

Amazon RDS is a managed relational database service for databases like MySQL, PostgreSQL, or SQL Server. It is intended for structured transactional workloads and does not provide native access to objects in S3. To query S3 data in RDS, developers would need to load it into tables first, which introduces additional complexity. Therefore, RDS is not a suitable option for serverless, direct querying of JSON data in S3. Considering all options, Athena is the correct choice because it allows developers to perform fast, serverless SQL queries directly on S3 data without provisioning any infrastructure.

Question 187 

Which service is used to protect APIs from malicious traffic such as SQL injection and XSS?

A) AWS WAF
B) Amazon GuardDuty
C) AWS Shield
D) Amazon Inspector

Answer:  A) AWS WAF

Explanation:

AWS WAF is a web application firewall that allows developers to define rules to block or allow HTTP and HTTPS requests based on patterns in the request, such as SQL injection (SQLi), cross-site scripting (XSS), or other malicious payloads. It can be deployed directly with services like Amazon CloudFront, Application Load Balancer, or API Gateway to protect web applications and APIs in real time. Developers can use pre-configured managed rule sets or define custom rules for fine-grained security. WAF also provides logging and metrics to monitor attack attempts and adjust rules dynamically.

Amazon GuardDuty is an intelligent threat detection service that continuously monitors for malicious activity or unauthorized behavior across AWS accounts and workloads. While it is highly effective at identifying suspicious patterns and potential intrusions, it is a detection tool rather than a prevention tool. GuardDuty does not block requests to APIs, so it cannot directly prevent attacks like SQL injection or XSS in real time.

AWS Shield is a managed Distributed Denial of Service (DDoS) protection service designed to safeguard applications from volumetric or protocol-level attacks. While Shield is critical for preventing large-scale denial of service attacks that could make APIs unavailable, it is not designed to filter or inspect the contents of HTTP requests for application-layer attacks like SQLi or XSS.

Amazon Inspector is a vulnerability assessment service that analyzes EC2 instances and container workloads to identify potential security risks or misconfigurations. It does not inspect live HTTP requests or protect APIs directly. Considering the need to block malicious input to APIs, AWS WAF is the correct choice because it provides real-time, rule-based protection against common web application attacks.

Question 188 

A developer needs a pub/sub messaging service that pushes messages to multiple subscribers. Which service is ideal?

A) Amazon SNS
B) Amazon SQS
C) AWS Lambda
D) Amazon MQ

Answer:  A) Amazon SNS

Explanation:

Amazon SNS (Simple Notification Service) is a fully managed pub/sub messaging service that allows a single message to be published to a topic and then pushed automatically to multiple subscribers, which can include SQS queues, Lambda functions, HTTP endpoints, or email addresses. SNS is highly scalable and designed for real-time message delivery, making it ideal for broadcast messaging scenarios where multiple systems need to receive the same message simultaneously.

Amazon SQS (Simple Queue Service) is a message queuing service that stores messages until they are retrieved by consumers. SQS supports decoupled architectures and ensures reliable delivery but is designed as a pull-based system, meaning subscribers must poll the queue to retrieve messages. Unlike SNS, SQS does not natively push messages to multiple endpoints.

AWS Lambda is a serverless compute service that executes code in response to events. While Lambda can process messages from SNS or SQS, it is not a messaging service itself. Lambda is best suited for event-driven processing rather than distributing messages to multiple subscribers directly.

Amazon MQ is a managed message broker service that supports traditional message broker protocols like AMQP, MQTT, and STOMP. While it supports pub/sub patterns, it is primarily designed for legacy applications that rely on broker-based architectures and is less scalable for serverless, high-throughput pub/sub scenarios. Considering the requirement for a service that can push messages to multiple subscribers in a scalable and serverless manner, SNS is the correct choice.

Question 189 

A serverless app stores image metadata and must support complex queries like sorting and pagination. Which service fits best?

A) Amazon DynamoDB with Global Secondary Indexes
B) Amazon S3
C) AWS Lambda
D) Amazon EFS

Answer:  A) DynamoDB with GSIs

Explanation:

Amazon DynamoDB is a fully managed NoSQL database that provides low-latency access to key-value and document data. When combined with Global Secondary Indexes (GSIs), it allows developers to perform complex queries, including sorting, filtering, and pagination, on attributes other than the primary key. GSIs enable scalable, flexible access patterns without denormalizing data, making DynamoDB a strong fit for serverless applications that need high performance for querying metadata.

Amazon S3 is an object storage service that can store large volumes of files, including images and metadata. However, S3 has limited query capabilities. While S3 Select allows querying specific parts of objects, it is not designed for complex queries across multiple objects, including sorting or pagination. Therefore, S3 alone is not suitable for applications requiring sophisticated query patterns.

AWS Lambda is a compute service for running code in response to events but does not provide persistent storage or query capabilities. Lambda can process metadata retrieved from a database, but it cannot serve as the primary storage or query engine for large-scale metadata.

Amazon EFS is a managed file system that provides shared file storage for EC2 instances. EFS supports hierarchical file structures but does not provide querying capabilities for structured or semi-structured metadata. For a serverless application requiring scalable, complex queries on metadata, DynamoDB with GSIs is the correct choice because it combines serverless scalability with rich query flexibility.

Question 190

A developer needs to automate creation and management of AWS resources using code. Which service is appropriate?

A) AWS CloudFormation
B) Amazon EC2
C) AWS CodeDeploy
D) AWS X-Ray

Answer:  A) AWS CloudFormation

Explanation: 

AWS CloudFormation is a fully managed service designed to implement infrastructure as code (IaC), enabling developers to define, provision, and manage AWS resources through code rather than manual configuration. With CloudFormation, infrastructure components such as EC2 instances, S3 buckets, Lambda functions, RDS databases, and more can be described in templates written in JSON or YAML. These templates specify the desired state of the infrastructure, including resource configurations, dependencies, and relationships. Once a template is deployed, CloudFormation automatically provisions and configures the resources in the correct order, ensuring that all dependencies are handled accurately. This approach allows developers and operations teams to automate repetitive tasks, reduce human error, and achieve consistency across multiple environments.

One of the key advantages of CloudFormation is that it provides a fully automated lifecycle management system. Templates can be versioned and reused, making it easier to replicate environments for development, testing, staging, or production. CloudFormation supports updates and deletions as well, so changes to infrastructure can be made systematically and safely. For example, updating a template can trigger a stack update that modifies only the necessary resources, without disrupting the rest of the environment. This capability is particularly valuable for organizations adopting DevOps practices, as it promotes repeatable and predictable infrastructure deployments.

Amazon EC2, by contrast, is a compute service that provides scalable virtual servers in the cloud. While EC2 instances are essential building blocks for running applications, EC2 alone does not provide automation for managing other AWS resources. Users can launch and configure servers manually or programmatically, but they would need additional scripting or orchestration tools to create complex infrastructure stacks. EC2 is therefore a component of the infrastructure rather than a tool for orchestrating or automating the creation of resources at scale.

AWS CodeDeploy is designed for automating application deployments to compute environments such as EC2 instances, Lambda functions, or on-premises servers. It focuses on delivering application code updates consistently and safely, but it does not manage the underlying infrastructure itself. CodeDeploy works alongside infrastructure management tools like CloudFormation but is not intended to replace them.

AWS X-Ray, on the other hand, is a distributed tracing service used to monitor and debug production applications. X-Ray provides insights into performance bottlenecks, latency issues, and errors, but it does not provision, configure, or manage infrastructure resources.

Given these options, CloudFormation is the correct choice for automating the creation and management of AWS resources using code. It offers a declarative, template-driven approach for full lifecycle management of resources, supports consistent and repeatable deployments, reduces manual intervention, and integrates seamlessly with other AWS services to enable reliable, automated infrastructure management.

Question 191 

Which service should be used for real-time WebSocket-based APIs?

A) Amazon API Gateway
B) Amazon CloudFront
C) Amazon S3
D) Amazon Route 53

Answer:  A) Amazon API Gateway

Explanation:

Amazon API Gateway is a fully managed service designed to create, deploy, and manage APIs at any scale. One of its key features is support for WebSocket APIs, which enables real-time, bidirectional communication between clients and servers. This makes it ideal for applications that require instant updates, such as chat applications, live dashboards, and gaming platforms. WebSocket APIs in API Gateway allow developers to define routes, manage connections, and handle messages efficiently, ensuring low latency and reliable delivery of real-time events.

Amazon CloudFront is a content delivery network (CDN) designed primarily to distribute static and dynamic web content globally with low latency. While CloudFront can accelerate API endpoints and serve cached content, it does not provide the necessary mechanisms to handle persistent, real-time WebSocket connections. It is optimized for distributing content quickly rather than managing live, stateful client-server communication.

Amazon S3 is a highly durable object storage service suitable for storing files, static website content, backups, and other unstructured data. While S3 is excellent for serving static assets or integrating with serverless architectures, it does not support WebSocket connections or real-time API functionality. S3 is focused on storage and retrieval rather than maintaining live sessions with clients.

Amazon Route 53 is a scalable DNS and domain name management service that directs internet traffic to AWS resources or external endpoints. While critical for routing requests to the appropriate infrastructure, Route 53 does not provide any API management, real-time communication, or WebSocket support. Its role is purely in DNS resolution and traffic management.

The correct choice is Amazon API Gateway because it is purpose-built for creating APIs, including RESTful and WebSocket APIs. It allows developers to manage routes, handle messages, and integrate with backend services or serverless functions like AWS Lambda. For real-time applications requiring persistent connections, API Gateway’s WebSocket support is essential, making it the service specifically designed for this use case.

Question 192 

A developer needs to validate API requests before they reach backend services. Which feature enables this?

A) API Gateway Request Validation
B) Amazon Cognito
C) AWS IAM
D) AWS X-Ray

Answer:  A) API Gateway Request Validation

Explanation: 

API Gateway Request Validation is a feature that ensures incoming API requests conform to expected formats before they are processed by backend services. This includes validating headers, query string parameters, and the request body against pre-defined JSON schemas. By performing validation at the API gateway level, developers can prevent malformed or unauthorized requests from reaching backend services, which helps maintain application stability and security.

Amazon Cognito is an identity management service that handles user authentication and authorization. It provides features such as user sign-up, sign-in, and access control via tokens. While Cognito ensures that only authenticated users can access an API, it does not perform detailed validation of request parameters or payloads. Cognito focuses on identity verification rather than request structure validation.

AWS Identity and Access Management (IAM) is a permissions management service that controls access to AWS resources. IAM allows developers to define roles and policies to restrict actions in AWS, such as reading S3 objects or invoking Lambda functions. While IAM enforces authorization, it does not inspect the contents of API requests or enforce schema compliance. Its scope is managing access control, not validating input data.

AWS X-Ray is a distributed tracing service that helps developers monitor and analyze requests as they travel through microservices architectures. X-Ray provides insights into performance bottlenecks, latency issues, and errors. Although useful for debugging and monitoring, X-Ray does not prevent invalid requests from reaching backend services. It is primarily an observability tool rather than a request validation mechanism.

API Gateway Request Validation is the correct choice because it actively checks requests before they reach backend systems, ensuring that only properly formatted requests are processed. This protects backend services from errors, reduces unnecessary processing, and allows developers to enforce strict API contracts efficiently, making it the ideal solution for pre-processing API requests.

Question 193 

Which service should be used to schedule serverless jobs on a time-based schedule?

A) Amazon EventBridge Scheduler
B) Amazon SQS
C) AWS Lambda
D) AWS Fargate

Answer:  A) EventBridge Scheduler

Explanation:

Amazon EventBridge Scheduler is a service designed to trigger tasks at scheduled times, using cron expressions or rate-based schedules. It allows developers to invoke AWS services, including Lambda functions, Step Functions, or other targets on a precise schedule. This is particularly useful for automating maintenance tasks, batch processing, and periodic notifications in a serverless architecture without requiring dedicated servers or manual intervention.

Amazon Simple Queue Service (SQS) is a fully managed message queuing service used for decoupling and buffering requests between distributed systems. While SQS reliably delivers messages for asynchronous processing, it does not provide built-in time-based scheduling. SQS can be combined with other services to achieve scheduled processing, but it is not inherently designed for triggering events on a specific schedule.

AWS Lambda is a serverless compute service that executes code in response to triggers such as API requests, S3 events, or messages from SQS. Lambda itself does not include native scheduling capabilities but can be invoked on a schedule using EventBridge Scheduler or CloudWatch Events. Lambda is therefore an execution engine rather than a scheduler.

AWS Fargate is a serverless container management service that runs containers without managing servers. Fargate can execute workloads continuously or in response to events, but it is primarily focused on containerized applications rather than time-based scheduling. While you can combine Fargate with EventBridge or other services to implement scheduled jobs, it does not directly provide cron-style triggers.

EventBridge Scheduler is the correct service for serverless scheduling because it is purpose-built to trigger actions on a predefined schedule. It integrates seamlessly with Lambda and other AWS targets, providing precise, automated, and serverless execution of time-based jobs without requiring additional orchestration or infrastructure management.

Question 194 

A developer needs to store and rotate database passwords automatically. Which service should be used?

A) AWS Secrets Manager
B) Parameter Store (Standard Tier)
C) S3 with SSE
D) DynamoDB

Answer:  A) AWS Secrets Manager

Explanation:

AWS Secrets Manager is a service specifically designed for securely storing, managing, and rotating secrets such as database credentials, API keys, and tokens. Secrets Manager can automatically rotate secrets according to a defined schedule, reducing operational overhead and enhancing security. It integrates with AWS services and applications, allowing seamless retrieval and encryption of secrets at runtime without exposing sensitive information in code.

Parameter Store (Standard Tier) is part of AWS Systems Manager and allows storage of configuration data and secrets. While it provides basic secret storage, it lacks automatic rotation features in the standard tier. This makes Parameter Store less suitable for dynamic credentials that require regular updates to maintain security best practices. The advanced tier of Parameter Store does provide rotation, but Secrets Manager remains more feature-rich.

Amazon S3 with Server-Side Encryption (SSE) provides secure storage for objects with encryption at rest. While S3 ensures encrypted storage, it is not designed for secret management, automatic rotation, or integration with applications for secret retrieval. Storing sensitive credentials in S3 requires additional logic for rotation and secure access, increasing operational complexity.

Amazon DynamoDB is a fast and scalable NoSQL database for structured data. Although you could technically store secrets in DynamoDB, it does not provide built-in encryption, rotation, or secret management capabilities. Using DynamoDB for passwords would require custom logic to manage rotation and security, which is inefficient and error-prone compared to a managed service.

AWS Secrets Manager is the correct choice because it provides secure storage, automated rotation, and seamless integration with applications. It eliminates manual management of credentials, reduces the risk of exposure, and ensures that database passwords and other sensitive secrets are consistently up-to-date, making it the best service for this use case.

Question 195 

Which service provides distributed caching to reduce read latency for applications?

A) Amazon ElastiCache
B) Amazon Aurora
C) AWS Lambda
D) Amazon EBS

Answer:  A) ElastiCache

Explanation:

Amazon ElastiCache is a fully managed service that provides in-memory caching using Redis or Memcached. By storing frequently accessed data in memory, ElastiCache reduces latency and alleviates pressure on backend databases, leading to faster application performance. It is ideal for read-heavy workloads such as session management, leaderboards, and frequently queried datasets.

Amazon Aurora is a relational database service designed for high performance and availability. While Aurora includes features like read replicas to scale read operations, it is not an in-memory cache. Accessing Aurora still involves database query latency, making it slower than a dedicated caching layer for frequently accessed data.

AWS Lambda is a serverless compute service that executes code in response to events. While Lambda can fetch and process data from a cache or database, it is not a caching service itself. Lambda focuses on computation and event-driven processing rather than reducing data retrieval latency through caching.

Amazon EBS provides persistent block storage for EC2 instances. EBS volumes are designed for durable storage but are not optimized for in-memory caching or low-latency reads. EBS is better suited for storing databases, logs, or file systems, rather than serving as a high-speed cache layer.

ElastiCache is the correct solution because it provides a fully managed in-memory caching layer that reduces read latency, improves application responsiveness, and offloads database workloads. It is specifically optimized for scenarios requiring fast data retrieval, making it the best choice for distributed caching in modern applications.

Question 196 

A developer wants an asynchronous compute service triggered by messages in a queue. Which service fits?

A) AWS Lambda
B) Amazon SNS
C) Amazon EC2
D) AWS Batch

Answer:  A) AWS Lambda

Explanation:

AWS Lambda is a serverless compute service that automatically runs code in response to events, including messages from an Amazon SQS queue. Lambda allows developers to write small, modular pieces of code that are triggered asynchronously whenever a message appears in a queue. The service manages the underlying infrastructure, including scaling, patching, and high availability, which frees developers from worrying about servers. Lambda’s event-driven model is particularly useful for building reactive applications where tasks are executed only when data arrives, making it cost-efficient and easy to maintain. This functionality is crucial for asynchronous processing where the timing of execution depends on incoming messages rather than a fixed schedule.

Amazon Simple Notification Service (SNS) is a fully managed publish/subscribe messaging service. SNS allows applications to send notifications to multiple subscribers simultaneously. While SNS supports event-driven architectures, it does not directly process messages or execute code. It primarily delivers messages to endpoints such as Lambda, SQS, HTTP/S endpoints, or email addresses. SNS works well for broadcasting messages to multiple consumers, but by itself, it is not a compute service capable of performing the actual processing of queued messages, which is what the developer requires in this scenario.

Amazon EC2 provides virtual servers in the cloud. It gives full control over operating systems, compute power, and network configurations. While EC2 instances can run any workload, they require manual provisioning, scaling, and maintenance. To process messages asynchronously from a queue on EC2, developers would need to implement a custom polling mechanism and manage instance scaling and availability themselves. This adds operational overhead and complexity, making EC2 less suitable for a fully managed, event-driven, serverless compute use case.

AWS Batch is a fully managed service for running batch computing workloads at scale. It is designed for large-scale parallel processing of jobs that can run to completion over hours or days. While Batch can process jobs asynchronously, it is primarily optimized for heavy compute workloads and batch processing rather than small, real-time tasks triggered by message events. Its scheduling model is not event-driven in the same way Lambda is and does not integrate directly with SQS for lightweight asynchronous message processing.

Lambda is the ideal choice because it provides a serverless, event-driven compute environment that automatically triggers functions in response to SQS messages. SNS is a messaging service without compute capabilities, EC2 requires manual management and polling for messages, and Batch is designed for large-scale batch jobs rather than lightweight asynchronous triggers. Lambda’s ability to automatically handle scaling, availability, and event triggers makes it the correct option for processing messages asynchronously from a queue.

Question 197 

Which service helps identify unused or underutilized AWS resources?

A) AWS Trusted Advisor
B) AWS CloudTrail
C) Amazon CloudWatch
D) Amazon GuardDuty

Answer:  A) Trusted Advisor

Explanation:

AWS Trusted Advisor is a service that provides recommendations to optimize AWS resources for cost, security, performance, and fault tolerance. One of its core capabilities is cost optimization, where it identifies idle or underutilized resources, such as EC2 instances, RDS databases, or EBS volumes that are not being fully utilized. Trusted Advisor scans the AWS environment and provides actionable insights, helping developers and administrators reduce unnecessary costs. It also suggests steps for improving efficiency, making it a valuable tool for organizations looking to optimize their AWS spend and resource usage.

AWS CloudTrail is primarily a logging service that records API activity across an AWS account. It enables auditing, governance, and compliance by capturing who did what and when across AWS resources. While CloudTrail is essential for security and compliance monitoring, it does not evaluate resource utilization or provide recommendations for unused resources. Its focus is on visibility and auditing rather than optimization.

Amazon CloudWatch is a monitoring and observability service that collects metrics, logs, and events from AWS resources. It is useful for tracking performance, setting alarms, and monitoring application health. CloudWatch can provide some insights into resource utilization through metrics such as CPU or memory usage, but it does not provide a comprehensive assessment of underutilized or idle resources with actionable cost-saving recommendations.

Amazon GuardDuty is a threat detection service that continuously monitors for malicious or unauthorized behavior in an AWS account. It analyzes AWS CloudTrail logs, VPC Flow Logs, and DNS logs to detect potential security threats. GuardDuty’s focus is security, and it does not provide information about resource utilization or idle resources, making it unrelated to cost optimization.

Trusted Advisor is the correct service for identifying unused or underutilized resources. CloudTrail helps with auditing, CloudWatch provides monitoring and performance insights, and GuardDuty focuses on security threats. Trusted Advisor uniquely combines visibility, actionable recommendations, and cost optimization, which aligns perfectly with the requirement of detecting unused or underutilized AWS resources.

Question 198 

A developer needs to deploy a containerized application using Kubernetes without managing nodes. Which service should be used?

A) Amazon EKS on Fargate
B) Amazon ECS
C) Amazon EC2
D) AWS Batch

Answer:  A) EKS on Fargate

Explanation:

Amazon EKS on Fargate provides a fully managed Kubernetes service where developers can run Kubernetes pods without managing underlying server instances. With Fargate, each pod is provisioned with the necessary compute and memory resources automatically, eliminating the need to manage EC2 instances, clusters, or scaling policies. This serverless model allows developers to focus entirely on application development and container orchestration rather than infrastructure management. EKS on Fargate integrates seamlessly with AWS networking, security, and logging services, providing a simplified and secure environment for running Kubernetes workloads.

Amazon ECS is a container orchestration service that allows developers to run Docker containers at scale. ECS supports both EC2-backed clusters and Fargate, but it does not provide a native Kubernetes API. ECS uses its own task and service definitions rather than Kubernetes constructs like pods, deployments, and services. While ECS can run containers serverlessly with Fargate, it does not meet the requirement if the application specifically needs Kubernetes compatibility.

Amazon EC2 provides virtual servers that can host containerized workloads, including Kubernetes clusters. Running Kubernetes on EC2 gives complete control over nodes, scaling, and networking, but it also requires substantial operational management. Developers would need to manage the cluster infrastructure, apply security patches, configure scaling policies, and monitor health, which contradicts the requirement for node-less, serverless container deployment.

AWS Batch is a service designed for running large-scale batch processing workloads. It can manage containerized jobs for batch computing, but it is not intended for running persistent Kubernetes workloads. Batch is optimized for processing queued or scheduled jobs rather than deploying containerized applications that need Kubernetes orchestration.

Therefore, EKS on Fargate is the ideal choice because it allows developers to run Kubernetes pods without managing any nodes. ECS can run containers but not Kubernetes pods natively, EC2 requires manual node management, and AWS Batch is for batch workloads, not interactive or persistent containerized applications. EKS Fargate perfectly fits the requirement for serverless Kubernetes deployment.

Question 199 

Which AWS service provides a fully managed GraphQL API backend?

A) AWS AppSync
B) Amazon API Gateway
C) Amazon RDS
D) AWS Lambda

Answer:  A) AWS AppSync

Explanation:

AWS AppSync is a fully managed service that allows developers to build GraphQL APIs with minimal operational overhead. It handles real-time data synchronization, offline access, and secure access to multiple data sources including DynamoDB, Lambda, and relational databases. AppSync abstracts away the backend complexity, providing resolvers that translate GraphQL queries into calls to different data sources. This allows developers to focus on building application features rather than managing servers, scaling, or integrating multiple APIs manually. Its native GraphQL support simplifies querying, filtering, and aggregating data, making it the best option for creating modern, data-driven applications.

Amazon API Gateway is a fully managed service that enables developers to create REST and WebSocket APIs. While it provides robust API management and integration with Lambda or other backends, it does not natively support GraphQL. Developers would need to implement a custom GraphQL server on Lambda or EC2 and manage resolvers themselves, adding operational overhead. API Gateway is excellent for RESTful applications but is not specialized for GraphQL.

Amazon RDS is a managed relational database service. While RDS is useful for storing structured data, it is not an API service and does not provide the features of GraphQL, such as schema-based queries, real-time subscriptions, or API-level data aggregation. Developers would need to implement their own backend layer to expose RDS data via GraphQL.

AWS Lambda is a serverless compute service that executes code in response to events. While Lambda can act as a backend for a GraphQL API, it is not a fully managed GraphQL service. Developers would need to build the GraphQL schema, handle resolvers, and integrate data sources manually. This increases development effort compared to using AppSync, which manages these aspects natively.

Question 200 

A developer wants version control for application code with AWS-native integration. Which service is suitable?

A) AWS CodeCommit
B) Amazon ECR
C) AWS CodePipeline
D) AWS Systems Manager

Answer:  A) AWS CodeCommit

Explanation:

AWS CodeCommit is a fully managed source control service that hosts secure Git repositories. Developers can store application code, track revisions, and collaborate with team members using Git commands or AWS Management Console integration. CodeCommit integrates seamlessly with other AWS developer tools, such as CodePipeline, CodeBuild, and CodeDeploy, enabling an end-to-end CI/CD workflow. The service automatically scales to handle large repositories and provides encryption at rest and in transit, ensuring secure code management. For organizations looking for native AWS version control, CodeCommit provides both flexibility and operational simplicity.

Amazon ECR (Elastic Container Registry) is a managed container image registry. It allows developers to store, manage, and deploy Docker container images. While ECR integrates with ECS, EKS, and Lambda for containerized deployments, it is not a version control system for application code. ECR tracks versions of container images, not source code changes, and therefore does not satisfy the requirement for version control of code itself.

AWS CodePipeline is a continuous integration and continuous delivery (CI/CD) service. It automates the build, test, and deployment stages of application development. While CodePipeline can integrate with CodeCommit or other repositories, it is not a version control system itself. Its purpose is to orchestrate pipelines rather than track and store code revisions.

AWS Systems Manager is a service for operational management of AWS resources. It provides capabilities such as configuration management, patching, and automation of operational tasks. Systems Manager does not handle application code versioning or repositories, so it does not meet the requirement for version control.