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
Most potent cholegogue is __________ 
Select and explain. 
A. Bile salts, B. Bile acids, C. CCK, D. GIP
C: CCK
Answer: C: CCK 
Explanation: Cholagogue causes gall bladder contraction. Most potent cholagogue in CCK.