Every time Luis gives his dog a treat, he shakes the box of treats first. His dog now reacts excitedly to the sound of the box of treats being shaken, even before Luis takes out a treat. In this situation, the treat is the ...

Treats is conditioned stimulus

Explanation:

The conditional stimulus is used in classical conditioning. The classical conditioning that was proposed by Ivan Pavlov. Classical conditioning works on behavior.

The conditioned response is when an animal or human being learned a new behavior. The conditioned stimulus is an important reward or stimulus that teach a new behavior to animals.

Thus here, Luis, every time gives his dog a treat. Treat play a role of conditioned response for Luis dog.