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: Microbiology
[{'content': 'Group A carbohydrate of Str. pyogenes cross reacts with human \nSelect and explain. \nA. Synovial fluid, B. Myocardium, C. Cardiac valves, D. Vascular intima', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]