This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
[{'content': 'Characteristic of Bacillus cereus food poisoning is \nSelect and explain. \nA. Presence of fever, B. Presence of pain in abdomen, C. Absence of vomiting, D. Absence of diarrhoea', 'role': 'user'}, {'content': "Answer: B \nExplanation: Bacillus cereus is an impoant cause of food poisoning. Two patterns: diarrheal and emetic. Diarrheal: associated with cooked meat and vegetables. Diarrhea and abdominal pain 8-16 hours after the ingestion of contaminated food. Vomiting rarely. Bacilli are not found in the fecal specimen of these patients. Emetic: associated with consumption of cooked rice, usually fried rice from restaurants. Nausea and vomiting 1-5 hours after the meal. Bacilli present in large numbers in cooked rice and fecal samples from these patients. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 253", 'role': 'assistant'}]