Final answer:
Trypsin is the protein-splitting enzyme found in pancreatic juice, responsible for the chemical digestion of proteins by hydrolyzing peptide bonds. The correct option is d.
Step-by-step explanation:
The protein-splitting enzyme found in pancreatic juice is trypsin. This enzyme is involved in the chemical digestion of proteins. It is produced in the pancreas as trypsinogen and then activated to trypsin in the small intestine where it catalyzes the hydrolysis of peptide bonds in protein chains, particularly those involving the carboxyl groups of the basic amino acids lysine and arginine.
Chymotrypsin and carboxypeptidase are also active enzymes in pancreatic juice that work alongside trypsin in protein digestion, attacking different peptide bonds and progressively breaking down protein molecules into peptides and amino acids. Additionally, pancreatic juice contains enzymes like pancreatic lipase for fat digestion and pancreatic nuclease for the digestion of nucleic acids, but trypsin is the specific protein-digesting enzyme among the options provided.