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 76 year old male comes with a history of frequent falls and difficulty in looking downwards and laterally. The diagnosis is : \nSelect and explain. \nA. Alzheimer's disease, B. Supranuclear palsy, C. Amyotropic lateral sclerosis, D. Oculornotor nerve palsy", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Answer is B (Supranuclear palsy):', 'role': 'assistant'}]