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': "The following is true of Naegele's pelvis : \nSelect and explain. \nA. Absence of one Ala, B. Both alae absent, C. Kyphotic spine, D. Triradiate pelvis", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Absence of one Ala', 'role': 'assistant'}]