When implementing a differential reinforcement of incompatible behavior DRI procedure the selection of a replacement behavior is critical for the interventions success The three essential characteristics for the replacement behavior are 1 Must be in the learners repertoire The learner must already be capable of performing the replacement behavior If the behavior is not in their repertoire there will be very few if any opportunities to reinforce it making the intervention ineffective New skill acquisition would need to precede or accompany the DRI implementation 2 Must be functionally equivalent The replacement behavior must serve the same function eg attention escape access to tangibles automatic reinforcement as the problem behavior it is designed to replace If the problem behavior is maintained by attention the replacement behavior must also reliably produce attention If the function is not met by the replacement behavior the problem behavior is likely to persist 3 Cannot occur simultaneously physically incompatible This is the defining feature of DRI The replacement behavior must be physically impossible or highly improbable to occur at the same time as the target problem behavior For example if the problem behavior is calling out a physically incompatible behavior might be raising hand quietly or sitting with hands in lap if calling out typically involves raising a hand and speaking loudly The physical incompatibility ensures that when the desired replacement behavior is occurring and being reinforced the problem behavior cannot occur thus leading to its reduction Options B C and D describe characteristics that either contradict these essentials or are not universally required for a DRI procedure