This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Physiology
Most impoant hormone for gallbladder contraction to release bile 
Select and explain. 
A. Secretion, B. CCK, C. VIP, D. Gastrin
B: CCK
Answer: B: CCK 
Explanation: This peptide hormone induces gallbladder contraction and the release of pancreatic enzymes in the gut. Ref: guyton and hall textbook of medical physiology 12th edition page number:421,422,423