In treating a 3-year-old child named Peter,Mary Cover Jones

A) used unconditional positive acceptance and empathic understanding to help Peter overcome his fear of rabbits.
B) was the first behavior therapist to use virtual reality therapy to eliminate a phobia.
C) conditioned a response that was incompatible with a previously learned response of fear in the presence of a tame rabbit.
D) used operant conditioning techniques to eliminate the child's fear of rabbits.

Mary Cover Jones used classical conditioning to condition a response that was incompatible with Peter's fear of rabbits. She presented a rabbit while Peter was eating food he enjoyed, gradually moving the rabbit closer until Peter was able to touch and even hold the rabbit without fear. This process is known as counterconditioning, and it created a response (enjoyment of food) that was incompatible with Peter's previous fear response, leading to the elimination of his phobia.