Hello, sorry this is a little late.
I believe the correct answer to your question, "an animals long period of inactivity during winter is called what" would be Hibernation.
Hibernation is when some animals (examples would be bears, and wild rabbits) sleep throughout the entire season of winter, when the temperature is too cold for them. They spend time before hibernation usually stocking up food, and creating a warm place for them to stay.
Hope this helps, and have a great day! :)
The best answer for this question would be:
D. Polymerase chain reaction
<span>It is used in molecular biology in order to create small fragments of the DNA. Those copies of the DNA mimic the happenings in the cell. This chain reaction is an efficient technique to further research on crimes.</span>
He's wondering what's going on in Life after a hard period of life