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': 'A child is presenting with vomiting and abdominal pain after 5 hours of eating some food. The most likely causative organism \nSelect and explain. \nA. Bacillus cereus, B. C. perfringens, C. Cl. Botulinum, D. V. cholerae', 'role': 'user'}, {'content': 'Answer: A \nExplanation: → Food poisoning presenting within 6 hours is seen:\n\nStaph aureus and\nB. cereus.\n\n→ Cl. Botulinum causes constipation (not diarrhea) and the incubation period is about 18-24 hours.\n→ V. cholerare has incubation period > 16 hours.', 'role': 'assistant'}]