After repeatedly pairing the sound of a bell with food being placed in a dog's mouth, the sound of the bell alone will make the dog salivate.
The dog's salivation to the sound of the bell is called the ___________.

A. conditioned stimulus (CS)
B. conditioned response (CR)
C. observable behavior
D. a voluntary action

Conditioned stimulus: In psychology, the term conditioned stimulus is also denoted as CS, and is one of the important parts in the classical conditioning theory. The conditioned stimulus is defined as a formerly neutral stimulus that triggers a conditioned response once it gets associated or connected with the UCS or unconditioned stimulus.

In other words, the conditioned stimulus is initially a neutral stimulus that produces conditioned response.after getting attached to UCS.

In the question above, the dog's salivation to the sound of the bell is called the conditioned stimulus.