The correct answer is b) amino acids.
Proteins are large, complex molecules that play many critical roles in the body. They are made up of smaller units called amino acids, which are linked together in long chains. There are 20 different amino acids that combine in various sequences to create a vast array of proteins, each with unique structures and functions.
Amino acids themselves are the building blocks of proteins, differing in their side chains, which influence the protein’s final shape and activity. In contrast, nucleotides are the building blocks of nucleic acids like DNA and RNA, fatty acids are components of lipids, and glucose is a simple sugar that serves as a primary energy source for cells. Hence, when it comes to proteins, they are exclusively made from amino acids.