Dr. Meyer is known for his difficult pop quizzes. Immediately before he springs a pop quiz on his students, he typically goes to the classroom door and closes it. Students soon learn to anticipate a pop quiz whenever Dr. Meyer closes the classroom door. Closing the door has become a(n):.a. conditioned stimulus. b. unconditioned stimulus. c. unconditioned response. d. conditioned response.

a. conditioned stimulus.

Explanation:

In the classical conditioning process, the conditioned stimulus which was a previously neutral stimulus, after becoming associated with the unconditioned stimulus generally initiates a trigger response.

For example, food is the unconditioned stimulus but the smell of food is the conditioned stimulus as it may generate the response of hunger in the subject.

According to the given situation, the difficult pop quiz is the unconditioned stimulus and closing the door is the conditioned stimulus. When the door closes the students can anticipate that Dr. Meyer is going to take a pop quiz.

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