This question addresses critical ethical considerations in Applied Behavior Analysis specifically client assent dignity and involvement in treatment planning when multiple effective interventions are available According to the BACB Professional and Ethical Compliance Code for Behavior Analysts clients have a right to effective treatment and should be involved in the planning and implementation of their services to the maximum extent possible When two interventions are equally effective the clients preference becomes a significant factor While the principle of least restrictiveness dictates that punishment should be considered only after less restrictive alternatives have been thoroughly evaluated and found ineffective this scenario explicitly states both interventions were effective Therefore respecting the clients informed preference as outlined in option B aligns with ethical guidelines promoting client autonomy and dignity Option A is incorrect because stating punishment should always be avoided is an overgeneralization there are specific circumstances where punishment procedures may be ethically justified and necessary Option C disregards the clients crucial role in treatment planning and undermines their dignity Option D is not universally applicable while parental consent is vital for minors for clients capable of expressing their preferences their assent is of primary importance especially when the interventions are proven effective