Jack always takes his dog out for a walk in the morning. Whenever Jack puts the leash on his dog, the dog gets very excited about going for a walk. In this scenario, the dog has learned to associate the leash with going for a walk through

classical conditioning

Classical conditioning, true

Explanation:

Classical conditioning is a learning approach whereby a previously unrelated, unconditioned stimulus is associated with a conditioned stimulus to elicit a conditioned response.

Putting the leash on the dog is the conditioned stimulus while the excitement shown by the dog is the conditioned response, going for a walk is the unconditioned stimulus.