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': 'Least common type of pelvis is : \nSelect and explain. \nA. Gynaecoid, B. Android, C. Mixed, D. Platypelloid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Platypelloid', 'role': 'assistant'}]