This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'Vaccine contraindicated in pregnancy \nSelect and explain. \nA. Hep A, B. Varicella, C. Rabies, D. Hep B', 'role': 'user'}, {'content': 'Answer: B \nExplanation: In pregnancy all live vaccines are contraindicated except yellow fever. Ref:- K Park, 24th ed; pg num:- 108', 'role': 'assistant'}]