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': 'Staphylococcus aureus is present in mayonnaise. The patient presents with nausea, vomiting, and abdominal pain, followed by diarrhea beginning 1-6 hours after ingestion of the toxin. The toxin is: \nSelect and explain. \nA. Not a preformed enterotoxin toxin, B. Preformed enterotoxin toxin, C. Preformed non enterotoxin toxin, D. Non preformed non enterotoxin toxin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Preformed enterotoxin toxin', 'role': 'assistant'}]