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': 'Food poisoning case with diarrhea within 6 hours- \nSelect and explain. \nA. Staph aureus, B. Cl. perfringens, C. Cl. botulinum, D. V. cholerae', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]