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': 'When the vex is well flexed presentation is : \nSelect and explain. \nA. Cehalic, B. Veex, C. Face, D. Brow', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Veex', 'role': 'assistant'}]