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': 'Which among the following is the commonest twin presentation? \nSelect and explain. \nA. Veex-brow, B. Veex-face, C. Veex-breech, D. Cephalic-cephalic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The most common presentations at admission for delivery are cephalic-cephalic, cephalic-breech, and cephalic- transverse. Compound, face, brow, and footling breech presentations are relatively common, especially if fetuses are small, amniotic fluid is excessive, or maternal parity is high. The presentation can often be asceained by sonography. Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 39. Multifetal Gestation. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.', 'role': 'assistant'}]