Final answer:
Pepsin enzymatically digests proteins, breaking them down into peptides in the stomach, with further digestion by other enzymes in the small intestine.
Step-by-step explanation:
Pepsin enzymatically digests proteins. This digestion process begins in the stomach, where pepsin breaks down intact proteins into peptides — short chains of four to nine amino acids. The digestion of proteins continues in the duodenum, where other enzymes such as trypsin, elastase, and chymotrypsin produced by the pancreas further break down the peptides. Eventually, peptidases reduce these peptides to free amino acids, which are then absorbed into the bloodstream through the small intestine.
Pepsin enzymatically digests proteins, breaking them down into peptides in the stomach, with further digestion by other enzymes in the small intestine.
Therefore, the answer to the student's question is c) Protein.