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': 'Most common type of Bening overian tumour during pregnancy is : \nSelect and explain. \nA. Simple serous cystoid, B. Mucinous cystoid, C. Teratoma, D. Papillary cystadenoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Simple serous cystoid', 'role': 'assistant'}]