This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Systemic Bacteriology Pa 1 (Gram Positive Cocci, Gram Negative Cocci), Subject name: Microbiology
[{'content': 'Which of the following streptococcal antigen cross reacts with synol fluid? \nSelect and explain. \nA. Carbohydrate (group A), B. Cell wall protein, C. Capsular hyaluronic acid, D. Peptidoglycan', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Antigens cross reactivity between Streptococcus antigens and the corresponding human antigen Streptococcal component Human tissue Capsular hyaluronic acid Synol fluid Cell wall protein Myocardium Group A carbohydrate Cardiac valves Cytoplasmic membrane antigen Vascular intima Peptidoglycans Skin antigens', 'role': 'assistant'}]