_____ is a learning process in which a previously neutral stimulus is repeatedly paired with an unconditioned stimulus that reflexively elicits an unconditioned response. Eventually, the conditioned stimulus itself will evoke the response.

(A) Classical conditioning
(B) Operant conditioning
(C) The Electra complex
(D) The Oedipus complex

Explanation: In Classical Conditioning, there are two stimuli linked together to produce a new response. One of them is the unconditioned stimulus (UCS), which produces unconditioned responses, and the other one is the neutral stimulus. This last stimulus doesn't produce a response, unless it is linked to a UCS. The first stimulus to appear is the neutral one, then the unconditioned ones takes place. For example, you eat too much burgers (neutral stimulus, it doesn't have a meaning yet), but then you get a stomachache (UCS). Now everytime you smell or eat a burger, you'll remember the time that you got sick and probably won't want to eat it (it's the new response).