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 Hirschsprung's disease:a) Pathology of myenteric plexus of Auerbachb) Blood in stoolsc) May involve small intestine rarelyd) Involved segment of intestine is dilatede) Present only in infant & children 
Select and explain. 
A. a, B. ac, C. ad, D. b
B: ac
Answer: B: ac 
Explanation: Small intestine may be involved rarely (~5%) - CSDT 13/e p1180 (11/e p1321)