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: Pathology
Fistula is most common in 
Select and explain. 
A. Crohn's disease, B. Ulcerative colitis, C. Infective entero colitis, D. Coeliac sprue
A: Crohn's disease
Answer: A: Crohn's disease 
Explanation: Clinical features Fibrosing strictures, paicularly of terminal ileum is common and requires surgical resection. Fistulas develop between loops of bowel and may also involve the urinary bladder, vagina, and abdominal or perianal skin. Perforations and peritoneal abscesses are common. TEXT BOOK O F ROBBINS BASIC PATHOLOGY NINTH EDITION PAGE.590