This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
[{'content': 'The dose of OPV, given at bih, in case of institutional deliveries is- \nSelect and explain. \nA. Zero dose OPV, B. Initial dose, C. Primary dose, D. First dose', 'role': 'user'}, {'content': 'Answer: A \nExplanation: .The dose of OPV, given at bih, in case of institutional deliveries is-zero dose OPV. ref:park&;s textbook,ed 22,pg no 184', 'role': 'assistant'}]