Identify the major digestive enzymes and where they act.

• A. Proteases digest carbohydrates in the mouth; amylase digests fats in the pancreas; lipase digests proteins in the stomach.
• B. Amylase in the mouth and pancreas digests carbohydrates; proteases (pepsin in stomach; trypsin and chymotrypsin in small intestine) digest proteins; lipase digests fats.
• C. Lactase is the main enzyme for fats; amylase in the liver; proteases in the pancreas.
• D. Amylase digests fats; proteases digest carbohydrates; lipase digests proteins.

Answer: (B)

Understanding how the major digestive enzymes work across the digestive tract helps explain why this option is correct. Carbohydrates are first targeted by amylase, which starts in the mouth from the saliva and then continues in the small intestine with pancreatic amylase, breaking down starches into simpler sugars. Proteins are digested by proteases in two key places: pepsin in the stomach begins protein breakdown in the acidic environment, and in the small intestine the pancreatic proteases trypsin and chymotrypsin finish the job, producing peptides that are further digested by other enzymes. Fats are mainly digested by lipase in the small intestine, with bile salts helping to emulsify fats and allow lipase to access triglycerides effectively. This pattern—amylase for carbohydrates in the mouth and pancreas, proteases (pepsin in the stomach and trypsin/chymotrypsin in the small intestine) for proteins, and lipase for fats—matches the statement described.