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
[{'content': "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 \nSelect and explain. \nA. a, B. ac, C. ad, D. b", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Small intestine may be involved rarely (~5%) - CSDT 13/e p1180 (11/e p1321)', 'role': 'assistant'}]