This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S., Subject name: Medicine
[{'content': 'Which cardiac valves have been replaced? \nSelect and explain. \nA. Aortic and mitral valves, B. Aortic and tricuspid valves, C. Mitral and tricuspid valves, D. Pulmonary and mitral valves', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Answer A. Aortic and mitral valvesThis patient had her mitral and aortic valves replaced with Starr-Edwards devices for severe rheumatic aortic and mitral stenosis.', 'role': 'assistant'}]