After Pavlov's Dogs Became Conditioned to Salivate at the Sound

Multiple Choice

After Pavlov's dogs became conditioned to salivate at the sound of the bell, he experimented with ringing the bell and then failing to present the dogs with any food right away. Soon they stopped salivating to the sound of the bell. This represents the process called __________

A) acquisition.
B) testing.
C) extinction.
D) spontaneous recovery.