Is/are an essential part of our nerves, spinal cord, brain, and cell membranes.
a. cellulite
b. adipose tissue
c. enzymes
d. skin

That would be B. Adipose tissue because it is like a padding that protects major organs like the kidneys and is a means of energy storage. 

It would be Adipose Tissue.
 
besides the fact of being loose connective tissue. it's a very big padding and also provides a lot of different cells, and even controls your storage of energy/fat to react to your hunger.

I got this answer right on my test.

The apple’s colors is red