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': 'The incidence of carcinoma of the caecum in relation to colonic adenocarcinoma is - \nSelect and explain. \nA. 2%, B. 4.50%, C. 20%, D. None', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'None'", 'role': 'assistant'}]