This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contraception, Subject name: Gynaecology & Obstetrics
[{'content': 'The contraceptive method with a failure rate of <3 is : \nSelect and explain. \nA. Copper-T, B. Vaginal sponge, C. Condom, D. Oral contraceptive pills', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The oral contraceptives are highly effective contraceptive methodThe failure rate is very low ( 0.3 c/o ), as ovulation is inhibitedRef: TEXTBOOK OF GYNAECOLOGY; Sheila Balakrishnan; SECOND EDITION; PAGE NO 366, 370', 'role': 'assistant'}]