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 about cholera is true - \nSelect and explain. \nA. Invasive, B. Endotoxin is released, C. Recent infections in india are of classical type, D. Vibriocidal antibody titre measures prevalence', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]