A) Correct option- DB) Explanation of correct option Both pepsin and trypsin are proteolytic enzymes. Pepsin is secreted in the stomach, whereas trypsin is a component of pancreatic juice. Pepsinogen is activated to pepsin in the stomach on exposure to hydrochloric acid. The optimum pH for the activity of pepsin is 1.8. Pepsin is a strong endopeptidase and breaks proteins into smaller molecules like peptones, proteOses and peptides. Trypsinogen is activated by the action of enterokinase into active trypsin. Enterokinase is secreted by the duodenal mucosa for activation of trypsinogen. Trypsin and chymotrypsin are endopeptidase types of enzymes and are active in alkaline pH i.e., 7.5 to 8. They dissociate proteins into peptones and proteoses