Amino acids are important to the body because they build .
a. carbohydrates
b. proteins
c. complex carbohydrates
d. simple sugars e. fats

The correct answer for the blank is- b. proteins.

Proteins are one of the four major macromolecules that are essential for the life forms ( as they are involved in most of the metabolic reactions). They are formed by long chains of small molecules that are called amino acids ( also referred as building blocks of proteins).

Amino acids are joined to each other using peptide bond in a process called translation. There are primarily 20 amino acids that make up proteins ( out of them 10 are essential that can not be synthesized by body and are obtained from external food source).

ok yes, but what is the question? as soon as you ask the actual question i will answer it. : )