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 maximum concentration of LIDOCAINE for topical block is: \nSelect and explain. \nA. 2%, B. 4%, C. 15%, D. 10%', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]