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 60-year old female presented with decreased movements for the last 2 years with rigidity and vertical large square wave jerks. The most likely diagnosis is - \nSelect and explain. \nA. Parkinson's disease, B. Lewy body dementia, C. Multisystem atrophy, D. Progressive supranuclear palsy", 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]