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': "All of the following casues subcortical dementia except- \nSelect and explain. \nA. Alzhimer's disease, B. Parkinsonism, C. HIV encephalopathy, D. Progressive supra nuclear palsy", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]