This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Physiology
[{'content': 'Trans-placental spread is least associated with \nSelect and explain. \nA. HBV, B. Rubella, C. HSV, D. HIV', 'role': 'user'}, {'content': "Answer: B \nExplanation: HSV is usually transmitted during delivery through an infected maternal genital tract. Transplacental transmission of virus and hospital-acquired spread from one neonate to another by hospital personnel or family may account for some cases. Ref ganong's review of medical physiology 25e 976", 'role': 'assistant'}]