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: Social & Preventive Medicine
[{'content': 'Which is the best way to prevent the spread of Polio during an epidemic? \nSelect and explain. \nA. OPV to all children, B. Isolation of the infected, C. Giving IPV to children, D. None of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Administration of OPV to all children is the best way to control polio epidemics. Other advantages of OPV are ease of administration, induction of humoral and intestinal immunity, quick production of antibodies in large propoion of vaccinees, it is inexpensive and excretion of virus by the vaccinee which inturn infects others and immunize them.', 'role': 'assistant'}]