Final answer:
The first step in setting up behavior therapy is conducting a functional analysis to understand the relationship between behaviors and the environment, as part of the operant conditioning approach.
Step-by-step explanation:
The first step a therapist is likely to take in setting up a behavior therapy treatment is A) Conducting a functional analysis. This approach involves assessing the relationships between a person's behaviors and their environment, identifying what rewards or punishments are maintaining the problematic behavior. By understanding the function of the behavior within the person's environment, the therapist can then modify the consequences or reinforcements to encourage more adaptive behaviors, a key concept in operant conditioning.
Behavior therapy relies on the principles of operant conditioning, where a target behavior is followed by reinforcement to strengthen it or punishment to weaken it, influencing the likelihood of the behavior being exhibited in the future. Thus, this form of therapy focuses on concrete actions and the modification of the environmental factors that influence these actions.