Biochemistry Mechanisms of Enzyme Action a734afc0 Chymotrypsinogen is a A Zymogen B Carboxypeptidase C Transaminase D Elastase High-Yield Explanation Ans. is 'a' i.e. Zymogen * Proteolytic digestive enzymes known as proteases have two main classes depending on specificity for the amino acids forming the peptide bond to be hydrolysed.