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': 'Melanoma should be excised with a margin of ? \nSelect and explain. \nA. 2 cm, B. 5 cm, C. 7 cm, D. 10 cm', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., 2 cm", 'role': 'assistant'}]