Proteins are made from which of the following?

Proteins are made from amino acids, which are the building blocks of protein. Each protein is composed of one or more chains of amino acids, and the specific sequence and structure of these amino acids determine the protein's function and characteristics. There are 20 different amino acids that combine in various ways to create the multitude of proteins found in living organisms.

The other options, such as fatty acids and vitamins, are important nutrients as well but serve different roles in the body. Fatty acids are primarily involved in the formation of lipids, which serve as a key source of energy and structural components of cell membranes. Vitamins are organic compounds that are essential for many metabolic processes, but they do not contribute to the structure of proteins.

While the correct answer appears to suggest that proteins could be made from all the listed substances, it's important to clarify that only amino acids specifically form proteins. Thus, the definitive answer to what proteins are made from is amino acids.