Homeostasis is maintaining stability in an organisms internal environment
The light would be best described as AN UNCONDITIONED STIMULUS.
An unconditioned stimulus refers to any stimulus which naturally evokes a response from the affected person. The response that is evoked is termed unconditioned response. In the question given above, the light is the unconditioned stimulus while the blinking is the unconditioned response.<span />
Answer:
The answer is:
D. The population must be very large.
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