Hardness is the answer I believe
Answer:
A. Extra thick fur
Explanation:
Because the winter is cold and little body fat and a dark colored fur will get it killed faster, but long ears can help the bunny hear the danger but I don't think there will be any predetors out in the harsh snow.
I think it would be the thrid
Im like 98% sure its B because ultra sounds hear the frequency's of the baby in the womb