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': 'Modern dental noble metal casting alloys generally have equiaxed fine grain structures because of the incorporation of small amounts of \nSelect and explain. \nA. Chromium, B. Indium, C. Iridium, D. Palladium', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]