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
Melanoma should be excised with a margin of ? 
Select and explain. 
A. 2 cm, B. 5 cm, C. 7 cm, D. 10 cm
A: 2 cm
Answer: A: 2 cm 
Explanation: Ans. is 'a' i.e., 2 cm