This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Gastro-intestinal hormone in the following is 
Select and explain. 
A. Pepsin, B. Ptyalin, C. Cholecystokinin, D. Trypsin
C: Cholecystokinin
Answer: C: Cholecystokinin 
Explanation: Option 'A' Pepsin is a proteolytic enzyme in gastric juice. Option 'B' Ptyalin or amylase is an amylolytic (carbohydrate splitting) enzyme in saliva. Option 'D' Trypsin is a proteolytic enzyme in pancreatic juice.
Cholecystokinin-Pancreozymin is a gastro-intestinal hormone that has actions on both pancreas and gall bladder.