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': 'Infective dose of salmonella typhi ? \nSelect and explain. \nA. 10 bacilli, B. 1000 bacilli, C. 103-106 bacilli, D. 1010 - 1012 bacilli', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., 103-106 bacilli In human volunteer experiments, the infective dose was found to be 103-106 bacilli.", 'role': 'assistant'}]