Answer:
B. The spinning motion of Earth.
It makes sure they are in perfect condition for it to go through the cell cycle easier
The answer would be D. Empiricality. Scientific Method can not, and will not deal with studies that are either for logic or for theism. This field may be beyond the scientific confirmability, meaning, it can not be proven by science, one example of this is the existence of a primary mover, or a God.
Yes. They do it to escape the winter. Hope it helps.