This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: general microbiology, Subject name: Microbiology
[{'content': 'An outbreak of sepsis caused by Staphylococcus aureus has occurred in the newborn nursery. You are called upon to investigate. According to your knowledge of the normal flora, what is the most likely source of the organism? \nSelect and explain. \nA. Nose, B. Colon, C. Vagina, D. Throat', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Nose is the common site of residence for Staphylococcus Ref: Textbook of Microbiology Baveja 4th ed pg:178', 'role': 'assistant'}]