Alan always turns the aquarium light on before putting fish food into the tank. after a while he notices that the fish swim to the top to look for the food as soon as he turns on the light. in this example, is the unconditioned stimulus.
a. presence of alan near the aquarium
b. aquarium light
c. fish swimming to the top
d. water temperature
e. fish food

e. fish food

Explanation:

Before choosing an answer we need to understand what unconditioned stimulus actually means. Unconditioned Stimulus is defined as something that triggers an automatic and natural response. Knowing this we can say that in the situation described in the question the Unconditioned Stimulus is the fish food as it creates a natural and automatic response of the fish moving to the top to eat it.

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