This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Non communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Best method of contrception in a commercial sex worker - \nSelect and explain. \nA. IUCD, B. OCP, C. Permanent sterilization, D. Barrier methods', 'role': 'user'}, {'content': "Answer: D \nExplanation: park's textbook of preventive and social medicine 23rd edition. *barrier method,non contraceptive advantages includes some protection from sexually transmitted disease ,a reduction in incidence of PID and some protection from risk of cervical cancer.", 'role': 'assistant'}]