Each year, as winter approaches, some species become inactive. they may sleep and use their body’s fat for energy during the cold season. migration hibernation imprinting conditioning plz hurry

Hibernation.

Explanation:

Some animals regulate their body temperature in steady state when  surroundings temperature changes. These animals are called endotherms. Examples of such animals are birds, mammals. Whereas, the body temperature of some animals change when there is change in the temperature of the surroundings. These animals are called ectotherms.  Examples of such animals are reptiles, amphibians. Ectotherms regulate their body temperature by many ways. They may use their body fat or by going into sleep, winter sleep (hibernation) and summer sleep (aestivation). Thus, hibernation is the correct option for this question.  

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