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': "Ball's operation is done for : \nSelect and explain. \nA. Ca. Cx, B. Ca. Ovary, C. Ca. Fallopian tube, D. Pruritus vulvae", 'role': 'user'}, {'content': 'Answer: D \nExplanation: Pruritus vulvae', 'role': 'assistant'}]