Which of the following is considered classical conditioning?

Pavlov’s dog experiments are the classic example of classical conditioning: Ivan Pavlov paired a neutral stimulus (a bell) with an unconditioned stimulus (food) until the dogs salivated to the bell alone—a learned, conditioned response to a previously neutral cue. This shows how organisms form automatic associations between stimuli. By contrast, Skinner’s box studied operant conditioning (behavior shaped by rewards and punishments), Harlow’s experiments explored attachment and comfort in infant monkeys, and Schrödinger’s cat is a quantum mechanics thought experiment. Memory tip: Pavlov → “Pavlovian” → pups that drool to a bell; Skinner → levers and pellets; Harlow → hugs and cloth mothers. Classical conditioning explains everyday phenomena