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.
The answer would be letter C
The answer is D. Run only full loads in the washing machine and dishwasher.
B doesn't seem like a good idea, C uses more water, and A would save water but not as much as the washing machine and dishwater use.
The number of species on Earth tagged at 8.7 million as of 2011.