Final answer:
Classical conditioning, also known as Pavlovian conditioning, refers to a form of treatment that involves repeated pairings of a stimulus with a very unpleasant stimulus to change an association.
Step-by-step explanation:
In classical conditioning, also known as Pavlovian conditioning, organisms learn to associate events or stimuli that repeatedly happen together. This form of conditioning involves pairing a stimulus with a very unpleasant stimulus to change an association. A famous example of classical conditioning is Ivan Pavlov's experiments with dogs, where the dogs learned to associate the ringing of a bell with receiving food.