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: Unknown
[{'content': 'Most common obstetrics nerve palsy? \nSelect and explain. \nA. Foot drop, B. Facial nerve, C. Median nerve, D. Radial nerve', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ref. DC Dutta's Textbook of Obstetrics. Pg 511\nThe commonest form of obstetric palsy encountered in puerperal period is foot drop. It is usually unilateral and appears shortly after delivery or during first day postpartum or so. It is thought to be\xa0 due to stretching of the lumbosacral trunk by the prolapsed intervertebral disc between L5 and S1.", 'role': 'assistant'}]