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': 'A 25-years-old male had severe headache followed by unconsciousness. CSF tap revealed red blood cells. Most likely diagnosis is - \nSelect and explain. \nA. Subdural hematoma, B. Embolism, C. Tumour, D. Ruptured aneurysm', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]