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': 'Most common cause of native valve endocarditis? \nSelect and explain. \nA. Staphylococcus aureus, B. Coagulase negative staphylococcus, C. Streptococcus, D. Enterococcus', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Staphylococcus aureus See above explanation.", 'role': 'assistant'}]