Grace whistles while tickling khaleel with a feather. eventually, khaleel starts to squirm and giggle every time grace whistles, even when he is not being tickled. in this example, squirming and giggling is a(n) a. unconditioned stimulus b. unconditioned response c. conditioned response d. conditioned stimulus

The answer is: C. conditioned response
conditioned response refers to a special response toward a certain stimulus that would not comes naturally under normal circumstances.
In the example above, Khaleel associate the whistle with the tickles that usually soon to follow, which ended up him making the gigles every-time he's hearing the whistle.

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