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.
Callous is another way to say it
The answer is C. Please mark as brainliest
Secondary structures are dependent upon hydrogen bonding. The two main types of secondary structure are the a-helix and the B-sheet. The a-helix is a right-handed coiled strand.