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: Anaesthesia
[{'content': 'High risk of post dural puncture headache is seen with \nSelect and explain. \nA. Spinal needle, B. Epidural needle, C. Both, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Large epidural needle has highest risk of post dural puncture headache.', 'role': 'assistant'}]