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 food poisoning in west \nSelect and explain. \nA. Vibrio cholera, B. S. aureus, C. Shigella, D. Salmonella', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]