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
Which of the following is a cholagogne- 
Select and explain. 
A. Secretin, B. CCK, C. VIP, D. Gastrin
B: CCK
Answer: B: CCK 
Explanation: Ans. is 'b' i.e., CCK Regulation of biliary secretion* The entry of bile into the duodenum increases either when the liver cells increase their bile secretion or when the gall bladder pours out its stored bile.1) Cholerectics:# Substances that increase hepatic bile secretion are called cholerectics.# The most importantcholerectics are bile salts themselves. Other cholerectic is secretin.2) Cholagogues:# Substances that cause gall bladder contraction to pour its bile are called cholagogues.# The most important cholagogue is cholecystokinin (CCK). Fatty acids and amino acids in the duodenum stimulate the release of CCK which causes gall bladder contraction.