Upon hydrolysis, what do proteins yield?

Proteins, when subjected to hydrolysis, are broken down into their constituent building blocks, which are amino acids. Hydrolysis is a biochemical process that involves the addition of water to cleave the peptide bonds that link amino acids together in a protein chain. This process effectively separates the polypeptide into individual amino acids, which can then be utilized by various biological processes such as the synthesis of new proteins, energy production, or conversion into other biologically important molecules.

The other choices provided do not accurately represent the products of protein hydrolysis. Fatty acids are the products of lipid hydrolysis, nucleotides are derived from nucleic acids, and simple sugars are products of carbohydrate hydrolysis. Hence, amino acids are the correct and specific outcome when proteins undergo hydrolysis.