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': 'Microorganism used as weap-on in biological terrorism is - \nSelect and explain. \nA. Smallpox virus, B. Rabies virus, C. Influenzae virus, D. Human narvovirus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]