I think it's C. Because hibernation is usually for animals living in Continental climates. I basically just eliminated the other answers until I got that one. One example for animals living in cold climates burrowing are Arctic Foxes.
My guess would have to be hydropower, since water isn't an un natural substance
Answer :<em> That trough time, a specie of animal, plant, bacteria can change.
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<em>When a life form reproduces, one of its"babies" may be different from its parents because of genetic mutation. </em>
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