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BCABA BACB Practice Test Questions and Exam Dumps

Question 1

When presenting extinction as a possible treatment option to a client and his or her family, it is MOST important for a behavior analyst to

A. assure them that extinction is supported in the literature as an effective procedure.
B. present it along with other interventions, including reinforcement based alternatives.
C. discuss the risks and benefits of using extinction and assure them that it is the best option.
D. explain his or her experience using extinction with similar cases.

Correct answer: B

Explanation:
When a behavior analyst discusses treatment options with a client and their family, the approach must align with ethical standards, informed consent practices, and a commitment to individualized and effective care. Extinction, while empirically supported, must be handled carefully due to the potential for side effects like extinction bursts or emotional responses. The best practice is to provide a comprehensive view of all viable strategies and collaborate with the client and family in the decision-making process.

Option A is partially correct in that it emphasizes evidence-based practice, but it is insufficient because simply telling the family that extinction is supported by the literature does not respect their right to be fully informed or give them a choice. While research backing is important, it’s not enough to justify using the intervention without considering alternatives or consequences.

Option B is the most appropriate choice. It reflects ethical practice and a client-centered approach. Presenting extinction alongside reinforcement-based alternatives helps ensure that the client and their family are aware of the full range of interventions, particularly those that are less likely to cause side effects or distress. Reinforcement-based strategies are typically preferred as they focus on teaching and increasing appropriate behaviors rather than simply suppressing undesirable ones. This choice also fosters collaborative treatment planning and respects the client’s autonomy.

Option C seems responsible at first glance because it includes discussing risks and benefits. However, the issue lies in the second part of the option — "assure them that it is the best option." This assumes a position of authority that overrides the shared decision-making process. While a behavior analyst can make recommendations, it is inappropriate to assert that one option is definitively the best without a thorough discussion and input from the client and family.

Option D, discussing the analyst’s experience, may help build rapport or trust, but personal experience is not a sufficient basis for selecting a treatment. Clinical decisions should be based on data, ethical considerations, and individualized assessments rather than anecdotal experience alone.

Ultimately, the guiding principles for behavior analysts include informed consent, transparency, client autonomy, and evidence-based practice. By presenting extinction as one option among others — especially those based on reinforcement — the analyst provides the client and their family with the necessary information to make an informed, collaborative decision. This respects their rights and ensures ethical integrity in clinical practice. Therefore, B is the best answer.

Question 2

A behavior analyst is asked to provide direct services requiring daily 1:1 interaction with a teen-aged client. The client does not speak but can communicate fluently using sign language. The behavior analyst knows some sign language but is not fluent. The BEST approach to this situation would be to

A. explain his level of competence in sign language to the family before beginning service.
B. hire a sign language interpreter to attend the sessions.
C. attend a workshop in sign language prior to beginning service.
D. refer the family to a behavior analyst fluent in sign language.

Correct answer: D

Explanation:
This question centers around ethical and professional decision-making, particularly in relation to competence and communication in applied behavior analysis. The scenario involves a nonverbal client who communicates fluently using sign language, and a behavior analyst who is not fluent in sign language but has some limited knowledge of it. The question asks what the most appropriate and professionally sound decision would be in this case.

When providing behavior-analytic services, one of the primary ethical standards is to practice only within the boundaries of one's competence, as outlined in codes such as the BACB Ethics Code for Behavior Analysts. This includes linguistic and cultural competence, particularly when communication is central to treatment.

Option A, which suggests explaining one's limited sign language skills to the family, is transparent and ethical in spirit, but it does not resolve the core issue. Even if the family is informed, the analyst would still be delivering services in a modality they are not qualified to use effectively. The behavior analyst’s role is not just to be honest, but to ensure competent service delivery. Therefore, while this option demonstrates integrity, it does not meet the standard for providing effective intervention.

Option B, hiring a sign language interpreter, could bridge the communication gap temporarily. However, this introduces potential challenges. Having a third party in every session can interfere with the direct interaction and rapport between the client and analyst. Additionally, behavior analysts are expected to engage directly with clients in ways that facilitate behavioral change, which can be hindered by reliance on an interpreter. This might be a short-term solution but is not ideal as a long-term, best-practice approach.

Option C, attending a workshop before beginning services, shows a desire to become more competent, but workshops do not typically provide fluency. Developing fluency in a language—especially to the level necessary for therapeutic communication—requires long-term practice and immersion, not just a brief course. Starting services based on workshop-level knowledge does not fulfill the ethical requirement of practicing within one’s area of competence.

Option D, referring the family to a behavior analyst fluent in sign language, is the most appropriate and ethically sound response. This ensures that the client receives the highest quality of care from someone who can communicate directly and fluently. It also demonstrates respect for the client’s needs and rights, and adherence to ethical guidelines regarding professional competence and cultural responsiveness. This option prioritizes the client's best interest and ensures effective service delivery without compromise.

In summary, the most ethically appropriate and client-centered decision is to refer the case to a behavior analyst who is fluent in sign language. This action upholds the integrity of the profession and ensures the client receives competent, effective, and respectful care.

Question 3

Fara has identified two procedures that have an equal probability of being effective. In order to select the better procedure, she should

A. choose the procedure that falls within the staff's level of competence.
B. determine which procedure is most clinically popular based on the rate of use by professionals.
C. select the procedure that best utilizes the existing funding stream.
D. use a random number table to rule out bias.

Correct answer: A

Explanation:
When selecting among equally effective procedures, ethical and practical considerations must guide the final choice. In this situation, both interventions are supported by evidence and have an equal likelihood of producing a positive outcome. The next step is to determine which procedure is more feasible and sustainable in the specific setting where it will be implemented. The competence of the staff is a critical factor in this evaluation.

Option A is the best answer because selecting a procedure that is within the staff’s level of competence ensures proper implementation and fidelity. Even the most well-designed intervention will likely fail or produce inconsistent results if those responsible for carrying it out do not have the training, experience, or confidence to do so accurately. Ensuring that a procedure is compatible with the staff’s existing skills increases the likelihood of consistent application, accurate data collection, and positive client outcomes. Furthermore, it supports staff morale and reduces the risk of treatment drift or errors. Ethical guidelines for behavior analysts emphasize using procedures that can be competently delivered by those implementing them.

Option B is not appropriate because choosing a procedure based solely on popularity or frequency of use among professionals does not necessarily mean it is appropriate for a particular context. Clinical popularity does not always equate to effectiveness or suitability within a given environment. Such an approach undermines individualized treatment planning and ignores context-specific variables like resources, staff skills, and client needs.

Option C considers funding streams, which are important from an administrative standpoint, but they should not outweigh considerations of treatment fidelity and ethical delivery. If a treatment is not implemented competently due to a mismatch with staff skills, the cost-effectiveness becomes irrelevant. Financial considerations should be secondary to ethical and clinical effectiveness when selecting among equally viable options.

Option D, using a random number table to avoid bias, may seem neutral and objective, but it disregards the practical and ethical responsibility to ensure that staff are capable of carrying out the procedure. Random selection ignores the human and contextual factors that determine treatment success, such as the existing skillset of the team and logistical realities of the setting.

In summary, when two interventions are equally effective based on available evidence, the procedure that can be implemented with the highest degree of fidelity and integrity should be chosen. This makes A, selecting the procedure that falls within the staff’s level of competence, the most responsible and effective decision.

Question 4

Which of the following would BEST contribute to a behavior analyst’s professional development?

A. attending a workshop that provides videotaped examples and practice activities for innovative interventions
B. reading articles from a peer-reviewed applied behavior analysis journal that describe techniques that are applicable to her client population
C. becoming a member of the Association for Behavior Analysis International, which is a rich resource for behavior analysts
D. contributing an article to the newsletter of the local Association for Behavior Analysis chapter

Correct answer: B

Explanation:
Professional development in the field of applied behavior analysis involves continuous learning, skill enhancement, and staying informed about the latest research-based practices. While all of the options in this question can contribute in some way to a behavior analyst’s professional growth, the question asks which one would best support such development. That requires identifying the option that has the greatest direct impact on the quality of clinical practice, informed decision-making, and evidence-based intervention.

Option A, attending a workshop with videotaped examples and practice activities, can certainly be valuable. Hands-on workshops often provide practical exposure to new techniques and allow for active engagement. However, the quality and scientific rigor of workshops can vary widely. While workshops may offer good supplemental learning opportunities, they do not always provide the depth, empirical backing, or peer-reviewed foundation that reading scholarly journal articles does. Also, workshops tend to be time-limited and focused on specific techniques, whereas professional development should include broader and deeper engagement with empirical literature.

Option B, reading peer-reviewed journal articles that describe techniques relevant to the behavior analyst’s client population, is the most direct and rigorous form of professional development. Peer-reviewed journals are the cornerstone of evidence-based practice. Articles published in these journals have undergone a formal review process by experts in the field, ensuring that the information presented is accurate, relevant, and scientifically validated. By consistently reading this literature, a behavior analyst not only stays up to date with emerging research but also sharpens critical thinking skills and deepens clinical insight. This enables the analyst to make more informed treatment decisions and to adapt or refine interventions based on solid evidence. This activity aligns strongly with the BACB’s emphasis on using current, evidence-based practices.

Option C, becoming a member of a professional organization such as the Association for Behavior Analysis International (ABAI), is certainly useful. Membership gives access to conferences, publications, and a network of professionals. However, joining such an organization, while beneficial for exposure and community building, does not in itself guarantee meaningful learning or improvement of clinical skill. Membership can support development, but only when accompanied by active engagement with the resources provided, such as reading journal content or attending workshops.

Option D, contributing an article to a newsletter, reflects initiative and community involvement, and it may offer professional recognition. However, this is more of an output activity—sharing knowledge—than an input activity that builds skills or deepens knowledge. Writing an article for a local newsletter may not require rigorous review or present opportunities to engage with cutting-edge research. While this can enhance visibility and communication skills, it is not the most effective tool for directly developing professional competence.

Therefore, although all four options have some value in contributing to professional development, reading peer-reviewed journal articles stands out as the most reliable, evidence-based, and consistent way to improve clinical knowledge, stay informed about advances in the field, and directly enhance professional skills. This makes it the best option among those presented.

Question 5

Before recruitment of participants for a research study begins, a behavior analyst needs to:

A. obtain consent from participant(s) or legal guardian(s) if necessary.
B. obtain institutional review board approval or equivalent (e.g., an ethics committee).
C. inform participants of their ability to withdraw from the study.
D. inform participants about ethical requirements and experimental procedures.

Correct answer: B

Explanation:
Before a behavior analyst begins the recruitment process for any research involving human participants, ethical practice and professional guidelines require obtaining approval from an Institutional Review Board (IRB) or an equivalent ethical review committee. This step is not just a formality; it is a safeguard that ensures the proposed research complies with ethical standards concerning the rights, safety, and well-being of the participants.

Option B is the correct answer because IRB approval must come before any interaction with potential participants, including recruitment. The IRB evaluates the study's methodology, consent procedures, risk-benefit analysis, confidentiality protections, and adherence to ethical standards. Without this approval, initiating recruitment or collecting any form of data would be premature and unethical. Behavior analysts, like all researchers working with human participants, must follow these established protocols to ensure the protection of subjects, prevent conflicts of interest, and maintain the integrity of the research.

Option A, obtaining consent from participants or guardians, is indeed a crucial step—but it occurs after IRB approval and once recruitment begins. Informed consent is part of the recruitment process and should only be pursued after the study has been vetted and approved by an ethical body. Proceeding with consent before IRB review violates professional conduct standards and bypasses a critical layer of ethical scrutiny.

Option C, informing participants of their right to withdraw, is a necessary part of the informed consent process. Participants must be clearly told that they can withdraw from the study at any point without any negative consequences. However, this disclosure also takes place during or after recruitment—not before it. Therefore, it is not the first step prior to initiating recruitment.

Option D, which involves explaining ethical requirements and experimental procedures, also falls under the umbrella of informed consent and participant education. While essential for ethical research conduct, this information is only communicated to participants after the study has been approved by the IRB and when recruitment begins. The IRB ensures that these elements are appropriately included in the study protocol and consent documents before they are presented to participants.

To summarize, the primary concern before initiating participant recruitment is ensuring that the study has been reviewed and approved by a body tasked with upholding ethical standards. Skipping this step would not only risk harm to participants but also invalidate the ethical legitimacy of the study. Hence, B, obtaining IRB or equivalent ethics approval, is the correct and most ethically responsible first step.

Question 6

Billy, a 20-year-old male, has the capacity to give consent for treatment. The behavior analyst has developed a program and explained it to Billy. Procedures, benefits, rights, and other information also were shown to him. The one element still needed for informed consent is approval from

A. Billy
B. clinical review committee
C. human rights committee
D. Billy's parents

Correct answer: A

Explanation:
Informed consent is a fundamental ethical and legal requirement in any professional field involving client services, including behavior analysis. The goal is to ensure that the individual receiving services understands the nature, purpose, benefits, risks, and alternatives of the proposed interventions before agreeing to proceed. In this scenario, the question provides important context: Billy is a 20-year-old adult and is explicitly described as having the capacity to give consent.

Capacity is the key factor in determining whether an individual is able to legally and ethically provide informed consent. If a person is over the age of majority (typically 18 in most jurisdictions) and possesses the cognitive and emotional ability to understand the information provided, then that individual is considered legally capable of consenting to or refusing treatment. In Billy’s case, he is 20 years old and is described as having the capacity to understand the explanation given about the treatment plan, including procedures, benefits, rights, and related information. Therefore, the person who must give approval for the plan to move forward is Billy himself.

Option A, Billy, is the correct answer because he is the client, he is an adult, and he is competent to make decisions about his care. For informed consent to be valid, it must be given voluntarily by a competent individual after receiving sufficient information. No additional approval is needed from others unless Billy were legally incapacitated, which the scenario does not indicate.

Option B, the clinical review committee, may sometimes be involved in reviewing treatment plans—especially those involving restrictive procedures—but their role is not to provide informed consent on behalf of the client. Their involvement is typically focused on professional oversight and ethical safeguards, not client authorization.

Option C, the human rights committee, is usually tasked with reviewing interventions that involve aversive or restrictive components or when clients are in residential or institutional care settings. However, this committee also does not serve as a substitute for informed consent from the client themselves. Their role is advisory and regulatory, not to provide personal consent on behalf of a capable adult.

Option D, Billy’s parents, would only be necessary if Billy were a minor or legally determined to be incompetent to make his own medical and treatment decisions. Since Billy is 20 years old and is described as capable, his parents have no legal authority to give or withhold consent for him. Involving parents in the conversation may be helpful or appropriate based on family dynamics, but their approval is not legally required in this context.

In summary, informed consent requires that the client receiving services understands the treatment and voluntarily agrees to it. Because Billy is an adult with the capacity to make decisions, the final step in the informed consent process is obtaining his direct approval.

Question 7

From an ethical standpoint, target behaviors and program goals should be selected

A. by service providers and staff members who are knowledgeable of the consumer's needs.
B. by the consumer or their representative in consultation with an interdisciplinary team.
C. so that they ultimately facilitate transition to independent living.
D. that most closely adhere to the standards of the community.

Correct answer: B

Explanation:
When determining which behaviors and goals to target in a behavior analytic intervention, ethical standards emphasize the importance of client-centered planning. This means the individual receiving services, or their legally authorized representative, must have a voice in the decision-making process. Therefore, option B is the correct choice because it reflects the collaborative and ethical approach recommended in professional codes of conduct such as the BACB Ethics Code.

By involving the consumer or their representative in setting goals—especially in collaboration with an interdisciplinary team—the process remains person-centered and respects the individual's autonomy, dignity, and preferences. This not only promotes ethical integrity but also increases the likelihood of client buy-in, engagement, and long-term success. The interdisciplinary team may include behavior analysts, medical professionals, educators, caregivers, and others who bring a holistic understanding of the client's life circumstances.

Option A, while sounding reasonable, falls short ethically because it centers decisions around service providers and staff without ensuring that the client or their representative is meaningfully involved. While knowledgeable staff certainly provide valuable input based on their expertise and observation, excluding the client from goal selection removes a key ethical requirement: respecting the individual's right to participate in decisions affecting their life.

Option C highlights an important objective—facilitating independent living—but it does not address the ethical process of goal selection. While preparing individuals for greater independence is often a desired outcome, setting goals solely based on this aim could lead to the imposition of values that may not align with what the individual actually wants or needs. Ethical practice demands that goals are based on collaboration and consent, not just long-term functionality.

Option D, which focuses on community standards, also misses the mark ethically. Although being socially appropriate and culturally sensitive is important, selecting goals based primarily on community expectations can risk pathologizing individual differences or promoting conformity at the expense of personal values. The primary concern must be the goals that are meaningful and valuable to the client, not what others think is appropriate.

In conclusion, ethical behavior analysis must involve the consumer in meaningful ways, empowering them or their guardians to take part in setting the direction of services. Option B encapsulates this responsibility by recognizing the client’s right to self-determination and collaboration, which is fundamental to ethical, effective, and respectful practice.

Question 8

Fred does not follow some of the directives imposed by the direct care staff. A behavior analyst has been asked to put a program in place that will get Fred to comply with all directives. The behavior analyst should FIRST

A. differentiate between compliance rates across different directives
B. request that staff provide a ratio of compliant behaviors to noncompliant ones
C. determine a list of potential reinforcers for the behavior program
D. consider the ethical implications of training Fred to comply with all directives

Correct answer: D

Explanation:
In this scenario, a behavior analyst has been asked to develop an intervention to increase Fred’s compliance with all directives given by the direct care staff. While compliance is often a relevant and functional goal, asking someone to comply with all directives raises important ethical questions. Therefore, before designing any kind of program, the analyst’s first responsibility is to assess whether the requested intervention aligns with ethical principles of autonomy, dignity, and individual rights.

Option D is the correct answer because it addresses the ethical responsibility of the behavior analyst. Compliance training can be beneficial when it promotes safety, independence, or cooperation in necessary routines. However, a blanket objective to increase compliance with all directives can become problematic if it leads to over-control, removes opportunities for the client to express preferences, or reinforces unequal power dynamics. Ethical guidelines such as those provided by the Behavior Analyst Certification Board (BACB) emphasize the importance of respecting client dignity, promoting client choice, and ensuring that interventions serve the client’s best interests. Therefore, the first step must be to reflect on whether training compliance to all staff directives is ethically justifiable, developmentally appropriate, and functionally necessary.

Option A, differentiating between compliance rates across different directives, would be useful once it has been determined that a compliance program is ethically acceptable. This step helps to identify which specific directives are being ignored and allows the analyst to design a targeted, individualized intervention. However, this step presumes that the intervention is appropriate, which must be considered only after ethical questions are addressed.

Option B, requesting staff to provide a ratio of compliant to noncompliant behaviors, is a data collection strategy that can help quantify Fred’s baseline behavior. While collecting this kind of data can support the intervention process, it is not the first step. It assumes the intervention is already appropriate to pursue, without questioning whether the demand for complete compliance is ethically sound.

Option C, identifying potential reinforcers, is part of a standard procedure for building behavior change programs. Reinforcement is often used to increase desirable behaviors, including compliance. Still, reinforcement should only be selected after the goals of the intervention have been confirmed to be appropriate. Designing a behavior change plan that involves reinforcers without first considering whether the plan is ethical could result in an intervention that promotes compliance for its own sake, even when it may not be in the client’s best interest.

In sum, the first responsibility of a behavior analyst is to ensure that all interventions are ethically justified. Encouraging someone to comply with all staff directives—without exception—could compromise the client’s autonomy and dignity. Before taking any further action, the analyst must pause to consider whether the intervention aligns with ethical standards and whether it serves the client’s individual goals and quality of life. Only after these ethical considerations have been addressed should the analyst proceed to the technical steps of assessment and treatment planning.

Question 9

A behavior analyst specializing in developmental disabilities is informed by a cousin at a family gathering that their 2-year-old child has just received a diagnosis of autism and severe intellectual disability. The cousin asks the behavior analyst for advice. 

Which statement BEST conforms to the ethical and professional standards for behavior analysts?

A. It would be unprofessional and unethical for the behavior analyst to advise a relative.
B. The behavior analyst can consult with their cousin, but only on an informal basis once the cousin hires their own behavior analyst.
C. Early intensive behavioral intervention may suit the child and family. The behavior analyst should suggest some people for the cousin to contact.
D. Tell the cousin that the child will benefit from behavioral intervention with the impact of the intervention depending on the specific treatment that is implemented.

Correct answer: C

Explanation:
This scenario raises important ethical issues around professional conduct, boundaries, and appropriate recommendations within the context of informal or potentially dual relationships. The best course of action for the behavior analyst is to respond in a way that is supportive yet within professional ethical boundaries. Therefore, option C represents the best choice.

By acknowledging that early intensive behavioral intervention (EIBI) may be helpful and suggesting referrals or trusted contacts, the behavior analyst remains within professional bounds. They are not taking on a clinical role with a relative, which could compromise objectivity and blur ethical lines. Instead, they are offering general guidance and connecting the family to resources that can provide more formal services. This aligns with ethical principles such as those outlined in the BACB Ethics Code, particularly the importance of avoiding multiple relationships that may impair professional judgment or risk exploitation.

Option A is too restrictive and incorrect. While it's true that behavior analysts must avoid dual relationships that impair objectivity or cause harm, providing a general recommendation or pointing someone toward services does not automatically violate ethical standards. It would be unethical to assume a formal role as a service provider to a family member, but giving supportive, non-clinical guidance is acceptable, especially when it involves referrals.

Option B contains a misleading condition. Suggesting that the behavior analyst can consult "informally" only after the cousin hires their own behavior analyst introduces confusion. If a family has already engaged a professional, the original behavior analyst should defer to that professional and avoid providing parallel advice, even informally. Consulting in any significant way, formal or informal, could still violate boundaries and contribute to dual relationships or professional overlap.

Option D assumes too much and could be ethically risky. Although the statement that behavioral intervention may help is generally accurate, telling the cousin that the child "will benefit" makes a clinical recommendation based on insufficient data. The behavior analyst has not assessed the child, and even though they may have strong clinical intuition, making any assertive statements about treatment effects without data is unprofessional. Ethical practice requires accurate, evidence-based communication that is grounded in thorough assessment.

In sum, option C is appropriate because it reflects a responsible and ethical approach. The behavior analyst provides a general statement about a widely accepted intervention and directs the family to others for further action. This avoids forming a dual relationship, respects the limitations of the setting, and helps the family take the next step in securing professional services.

Question 10

From an ethical standpoint, which source provides the MOST appropriate information for justifying implementation of a program to change a person's behavior?

A. daily reports from the direct care staff who work with the person routinely
B. graphed data from the program staff who observe the person regularly
C. written recommendations from the medical staff who treat the person on a regular basis
D. written requests from the administrative staff who are ultimately responsible for the person's care

Correct answer: B

Explanation:
In the field of behavior analysis, ethical decision-making is rooted in objective evidence rather than subjective opinion, administrative preference, or indirect observations. The most ethically defensible way to justify the implementation of a behavioral program is by using data that reflects observable and measurable aspects of behavior over time. Option B — graphed data from the program staff who observe the person regularly — is the only choice that meets this critical standard.

Graphed data represents a formal, objective account of behavior collected through systematic observation. Behavior analysts rely heavily on such data to determine whether a behavior occurs frequently enough to justify intervention, whether it poses any risk to the individual or others, and whether it affects the individual’s quality of life. Graphed data also allow for analysis of behavior patterns over time, identification of environmental variables, and the evaluation of the effectiveness of previous or current interventions. Without objective data, any program that is developed risks being based on biased opinions, administrative convenience, or unverified anecdotal concerns.

Option A refers to daily reports from direct care staff. While this information may be helpful for context and preliminary insight, it is often narrative or anecdotal. Such reports can be biased by memory limitations, personal interpretations, or emotional responses. Though staff insights are valuable, especially when they work closely with the individual, their observations must be verified by structured data collection before being used as the primary justification for behavior change programming.

Option C refers to written recommendations from medical staff. While medical professionals bring expertise in diagnosing and treating physiological or psychiatric issues, their assessments are not a substitute for behavioral data when it comes to designing behavioral interventions. A doctor may recommend a behavior support program based on clinical impressions, but without data collected in the client’s natural environment, these recommendations alone are not sufficient to ethically justify the implementation of a behavior change program.

Option D, which references written requests from administrative staff, is even further removed from ethical justification. Administrators may be responsible for operational decisions or organizational policies, but they are unlikely to have first-hand behavioral data or training in behavior analysis. Their motivations may be influenced by staffing issues, funding, or compliance with regulations — none of which should take precedence over individualized, data-based decision-making that prioritizes the client's well-being.

Ethical guidelines in applied behavior analysis — such as those outlined in the BACB’s Ethics Code — stress the importance of using data to inform all aspects of assessment, goal setting, and treatment planning. Interventions must be based on clear, measurable needs demonstrated through systematic observation. In addition, ethical practice requires that interventions be tailored to the individual, serve their best interest, and be supported by ongoing data collection and review.

In summary, among the choices provided, graphed data is the most appropriate and ethically defensible source of information for justifying a behavioral intervention. It aligns with the foundational principles of evidence-based practice in behavior analysis and ensures that decisions are made in the client’s best interest based on reliable, observable facts.