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
Which of the following is not associated with Crohn's disease: March 2005 
Select and explain. 
A. Fistula, B. Stricture, C. Sclerosing cholangitis, D. None
D: None
Answer: D: None 
Explanation: Ans. None of the option