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': 'Commonest twin presentation is : \nSelect and explain. \nA. Veex-brow, B. Veex-face, C. Veex-breech, D. Veex-veex', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Veex-veex', 'role': 'assistant'}]