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: Surgery
Most common cause of obstructive jaundice 
Select and explain. 
A. Periampullary carcinoma, B. Carcinoma gall bladder, C. Carcinoma head of pancreas, D. CBD stones
D: CBD stones
Answer: D: CBD stones 
Explanation: Most common cause of obstructive jaundice is CBD stones.It can also be caused by Carcinoma head of pancreas,Carcinoma of periampullary region,Carcinoma of gallbladder,Biliary stricture,& Viral hepatitis.Obstructive jaundice caused by gallstones is intermittent while in the rest of the cases,jaundice progressively increases over weeks. Reference:SRB's manual of surgery,5th edition,page no:651