This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'All vaccines are contraindicated in pregnancy except \nSelect and explain. \nA. BCG  Vaccine, B. Measles Vaccines, C. OPV Vaccine, D. Yellow fever vaccine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: All live vaccines are contraindicated in pregnancy except yellow fever vaccine.', 'role': 'assistant'}]