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': 'A postspinal headache is due to - \nSelect and explain. \nA. Injury to spinal cord, B. CSF leak from dura, C. Meningitis, D. Raised intracranial pressure', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans: B', 'role': 'assistant'}]