Final answer:
The learned ability to give a conditioned response only to the original conditioned stimulus is known as stimulus discrimination.
Step-by-step explanation:
After a response has been classically conditioned, learning to give the conditioned response (CR) only to the original conditioned stimulus (CS) illustrates stimulus discrimination. This is a process where an organism learns to respond differently to similar stimuli, demonstrating the conditioned response solely to the conditioned stimulus. For example, Pavlov's dogs learned to salivate only at the sound of the specific tone that was paired with food, differentiating it from other similar tones.