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: Gynaecology & Obstetrics
[{'content': "Sex chromosome pattern in Klinefelter's syndrome is: March 2004 \nSelect and explain. \nA. XXY, B. XO, C. XX, D. XY", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A i.e. XXY', 'role': 'assistant'}]