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': 'Percentage of tin in low copper alloy is \nSelect and explain. \nA. 30-35%, B. 26-28%, C. 13-32%, D. 22-30%', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]