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': 'Copper content in low copper amalgams is: \nSelect and explain. \nA. 6%, B. 12-30%, C. 29%, D. 19%', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]