In classical conditioning, the response evoked by an unconditioned stimulus is called what?

• A. Stimulus
• B. Conditioned Response
• C. Unconditioned Response (UCR)
• D. Acquisition

Answer: (C)

In classical conditioning, the innate reflex triggered by an unconditioned stimulus is called the unconditioned response. This response happens automatically without any learning—for example, salivating when food is presented to a hungry animal. The unconditioned stimulus is what naturally evokes that reflex. After pairing a neutral signal with the unconditioned stimulus, the neutral becomes a conditioned stimulus, and the learned response to that signal is a conditioned response. The term you’re looking for is unconditioned response, often abbreviated UCR. The other terms refer to different ideas: a stimulus is anything that elicits a response, acquisition is the process of learning the association, and a conditioned response is the response to the conditioned stimulus after learning.