A naturally occurring stimulus that leads to an involuntary (reflex) response is a(n)

• A. unconditioned stimulus.
• B. unconditioned response.
• C. neutral stimulus.
• D. conditioned stimulus.

Answer: (A)

Verified step by step guidance

1. Understand the concept of classical conditioning, which involves learning through association. It was first described by Ivan Pavlov.
2. Identify the key components of classical conditioning: unconditioned stimulus (UCS), unconditioned response (UCR), conditioned stimulus (CS), and conditioned response (CR).
3. Recognize that an unconditioned stimulus (UCS) is a stimulus that naturally and automatically triggers a response without any prior learning.
4. Consider the definition of an unconditioned response (UCR), which is the automatic and involuntary response to the unconditioned stimulus.
5. Differentiate between the unconditioned stimulus and other types of stimuli, such as a neutral stimulus (which initially does not trigger a response) and a conditioned stimulus (which triggers a response after association with the UCS).