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': 'Which of the following bacteria act by increasing c-AMP - \nSelect and explain. \nA. Vibrio cholera, B. Staphylococcus aureus, C. E. coli, heat stable toxin, D. Salmonella', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Toxin acts by cAMP\xa0are: LT of E.coli, Cholera toxin, Pertussis toxin, Anthrax toxin (edema factor).', 'role': 'assistant'}]