This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetics, Subject name: Medicine
[{'content': 'Barr body is seen in: \nSelect and explain. \nA. Turners syndrome, B. Klinefelters syndrome, C. Testicular feminisation, D. 46 XY', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans: b', 'role': 'assistant'}]