This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Regional Anesthesia, Subject name: Anaesthesia
[{'content': "Tuohy's needle is used for: \nSelect and explain. \nA. Spinal block, B. Epidural block, C. Saddle block, D. Brachial plexus block", 'role': 'user'}, {'content': 'Answer: B \nExplanation: This is tuohy needle used for epidural anaesthesia', 'role': 'assistant'}]