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': 'Which one of the following Gram positive organism is most common cause of UTI among sexually active women : \nSelect and explain. \nA. Staphylococcus epidermidis, B. Staphylococcus aureus, C. Staphylococcus saprophyticus, D. Enterococcus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Remember:\n\nMC cause of UTI - E. coli\nMC cause of nosocomial UTI - E. coli\nMC nosocomial infection - UTI\nS. saprophyticus produce UTI characteristically in sexually active young woman\nEnterococci and S.aureus cause infections in patients with renal stones or previous instrumentation or surgery.', 'role': 'assistant'}]