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': 'According to WHO classification of ovarian tumours, Brenner tumor of ovary belongs to: \nSelect and explain. \nA. Epithelial tumours, B. Sex cord stromal tumours, C. Germ cell tumours, D. Metastatic tumours', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Cancer or Ovary', 'role': 'assistant'}]