This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of health and disease, Subject name: Social & Preventive Medicine
[{'content': 'Which of the following Intrauterine device has a minimum failure rate \nSelect and explain. \nA. Progestase, B. Cu T-380 A, C. Levonorgestrel IUD, D. T Cu -200', 'role': 'user'}, {'content': "Answer: C \nExplanation: Mirena (Levonorgestrel IUD) has least failure rate among IUD's Contraceptive implants (Implanon) have the least failure rates among all contraceptive methods. Ref : Park 23rd edition Pgno : 496", 'role': 'assistant'}]