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: Dental
[{'content': '8% SnF2 contains how much % of flouride \nSelect and explain. \nA. 1%, B. 2%, C. 3%, D. 4%', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]