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: Surgery
Most common cause of acute pancreatitis is - 
Select and explain. 
A. Biliary tract diseases, B. Alcoholism, C. Post traumatic, D. Idiopathic
A: Biliary tract diseases
Answer: A: Biliary tract diseases 
Explanation: None