Final answer:
The ability to distinguish between a conditioned stimulus and a similar but different stimulus is known as stimulus discrimination.
Step-by-step explanation:
The ability of an organism to be able to distinguish between a conditioned stimulus (CS) and a similar stimulus that is not the CS is called stimulus discrimination. This learning process is crucial in classical conditioning and refers to the organism demonstrating the conditioned response only to the conditioned stimulus, and not to other similar stimuli.
An example of this can be seen when Pavlov's dogs responded only to the specific tone that predicted food, and not to other similar sounds. On the other hand, stimulus generalization occurs when an organism begins to show the conditioned response to stimuli that are similar to the conditioned stimulus. The more similar the stimuli are, the more likely the conditioned response will be triggered. So, the correct answer to the student's question is b. discrimination.