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': 'The ADA specification No 1 for composition of amalgam alloy, recommends, \nSelect and explain. \nA. 65% silver, 32% tin and 3% copper, B. 49% silver, 32% tin and 19% copper, C. 65% silver, 29% tin and 5-6% copper, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]