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 is a RNA virus? \nSelect and explain. \nA. Measles virus, B. Herpes virus, C. Papaya virus, D. Adeno virus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]