A Cat Is Classically Conditioned to Purr When It Hears

Multiple Choice

A cat is classically conditioned to purr when it hears the refrigerator door open,because it contains the cat food.But the cat does not purr when it hears the pantry door open.The fact that the cat only purrs when the refrigerator door opens is most likely a result of

A) stimulus discrimination.
B) spontaneous recovery.
C) stimulus generalization.
D) extinction.