When Tabitha Enters the Dentist's Office, the Sound of the Drill

Multiple Choice

When Tabitha enters the dentist's office, the sound of the drill makes her wince, even though she doesn't currently feel any pain. She also hears the loud squeaking of the main door as each patient enters and leaves, but this sound does not make her wince. Not wincing in response to the sound of the squeaking door is BEST described as an example of:

A) extinction.
B) discrimination.
C) generalization.
D) reinforcement.