This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Census, SRS, NFHS, DLHS, VRS, Subject name: Social & Preventive Medicine
[{'content': 'The most cost-effective family planning method is- \nSelect and explain. \nA. Vasectomy, B. Barrier method, C. DMPA, D. Oral pills', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Vasectomy and IUD are one of the most cost-effective methods of contraception. Most impoant demographic feility indicator is -NRR. To achieve NRR-1, CPR should be >60%, ideal contraception is sterilization .', 'role': 'assistant'}]