an instinct an inherited trait a learned behavior a conscious behavior
I gave my students this multiple choice question: In an experiment, a scientist named Pavlov rang a bell before he fed his dogs, which made the dogs drool. Soon the dogs would drool when they heard the bell, even if they did not receive any food. What type of response did the dogs exhibit?

Only one answer is correct among these 4 choices:
- an instinct
- an inherited trait
- a learned behavior
- a conscious behavior

Could you tell me which one is correct?

a learned behavior