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': 'In carriers, staphylococci are found in the following sites except - \nSelect and explain. \nA. Throat, B. Nose, C. Skin, D. Anal canal', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Epidemiology of staph. aureus infection \n\nS. aureus is part of normal human flora. The anterior nares are the most frequent site of human colonization although the skin (especially when damaged), vagina, axilla, perineum and oropharynx may also be colonized.\n\n\nSome carriers, called shedders disseminate very large numbers of cocci for prolonged periods.\n\n\nStaph aureus is the most common cause of surgical wound infection and is second only to coagulase-negative staph. as a cause of primary bacteremia.\nMost individuals who develop S. aureus infections do so with their own colonizing strains. Most common route of infection is skin.\nThe oldest, simplest and the most effective method of checking hospital cross-infection is hand washing.', 'role': 'assistant'}]