Because it's a site of heat production which type of connective tissues found in animals that hibernate during the cold winter months

a. dense fibrous connective tissue

b. white adipose tissue

c. reticular fibrous connective tissue

d. brown adipose tissue

I think the correct answer would be D. Brown adipose tissue is the connective tissue that can be found in animals that hibernate during the cold winter months because it is a site for heat production. It is also called as brown fat and is found in almost all of the mammals. Its main function is for thermoregulation.  It functions to transfer the energy from the food being processed in the body into heat energy which is then used by living organisms to maintain body heat especially during cold conditions. This tissue or fat is abundant in hibernating mammals and in newborn babies. Also, it is present and active in adults.

They are all in a iving organism.