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': "Hirschsprung's disease involves which region of intestine: March 2005 \nSelect and explain. \nA. Colon, B. Rectum, C. Rectosigmoid pa, D. Terminal ileum", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C: Rectosigmoid pa', 'role': 'assistant'}]