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
The most impoant hormone that increases gallbladder contraction after a fatty meal is: 
Select and explain. 
A. Gastrin, B. Secretin, C. CCK, D. GIP
C: CCK
Answer: C: CCK 
Explanation: Ans. c. CCK