This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Demography and family planning, Subject name: Social & Preventive Medicine
[{'content': 'Chemical used in vaginal sponge is \nSelect and explain. \nA. Ethynil estradiol, B. Progesterone, C. Mifepristone, D. Nonoxynol-9', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Vaginal sponge is a small polyurethane foam sponge saturated with spermicide, nonoxynol-9 It comes under barrier method of contraception Reference : Park&;s textbook of preventive and social medicine, 23rd edition, Page no: 495', 'role': 'assistant'}]