This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bile duct, Subject name: Surgery
The most common cause of suppurative cholangitis is:- 
Select and explain. 
A. Stone in common bile duct, B. Cancer of the ampulla of vater, C. Choledochal cyst, D. Empyema of gallbladder
A: Stone in common bile duct
Answer: A: Stone in common bile duct 
Explanation: CHOLANGITIS Ascending bacterial infection of the biliary ductal system with obstruction MC cause of acute cholangitis is choledocholithiasis MC causative organism- E. coli, Klebsiella pneumonia, Streptococcus faecalis, & Bacteroid fragills. Treatment Initial treatment: IV antibiotics & aggressive hydration.