This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contraceptives, Subject name: Gynaecology & Obstetrics
[{'content': "Low dose OCP's contain: \nSelect and explain. \nA. Levonorgestrel, B. Desogestrel, C. Norgestrel, D. Norethisterone", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. is b, i.e. DesogestrelRef: Reffcoate 7th/ed, p802, Dutta Gynae 6th/ed, p465; SK Chaudhary 7th/ed, p120-130Low dose OCPs on 3rd generation OCP have desogestrel.', 'role': 'assistant'}]