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: Medicine
[{'content': 'Which of the following is the most common cause of late neurological deterioration in a case of cerebro- vascular accident - \nSelect and explain. \nA. Rebleeding, B. Vasospasm, C. Embolism, D. Hydrocephalus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]