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': 'Discolored areas seen through the enamel in the teeth that have amalgam restorations are known as \nSelect and explain. \nA. Amalgam tattoos, B. Amalgam overhangs, C. Amalgam blues, D. Amalgam ditchings', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]