In classical conditioning, Unconditioned response and conditioned response are the same behavior, opposite behavior, different behavior or the same stimulus?

the same behavior

Explanation:

In classical conditioning, the unconditioned response becomes the conditioned response after continuous repetition of the conditioned and unconditioned stimulus for a period of time.

For example, before conditioning, presentation of food (unconditioned stimulus) produces an unconditioned response (salivation). However, after conditioning, the unconditioned response becomes the conditioned response.