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
True about Ogilive's syndrome are all except: 
Select and explain. 
A. It is caused by mechanical obstruction of the colon, B. It involves entire / part of the large colon, C. It occurs after previous surgery, D. It occurs commonly after narcotic use
A: It is caused by mechanical obstruction of the colon
Answer: A: It is caused by mechanical obstruction of the colon 
Explanation: None