Final answer:
The reinforcement of Phoebe's phobic behavior is described by B. F. Skinner's theory of behaviorism, specifically operant conditioning where behavior is influenced by consequences like reinforcements.
Step-by-step explanation:
Phoebe has been reinforced for her phobic behavior, which aligns with the theories of B. F. Skinner, a significant figure in the behaviorist branch of psychology. Skinner emphasized that behavior is influenced by its consequences, particularly reinforcements and punishments, which are central to his theory of operant conditioning. In Phoebe's case, the reinforcement for her avoidance behavior could be negative reinforcement (escape from the feared object) or positive reinforcement (attention from others), both of which increase the likelihood that the phobia-related avoidance behavior will continue. Skinner was an influential behaviorist who studied how behavior is affected by its consequences, emphasizing reinforcement and punishment as major factors in driving behavior.