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': 'An 80 year old man has a history of progressive gait disturbance and incontinence which had been attributed to old age and prostatism. For the past 4 months he has been forgetful and confused. He has a history of head trauma 25 years ago. His head CT is shown below .The most likely diagnosis \nSelect and explain. \nA. Alzheimer’s disease, B. Creutzfeldt – jakob disease, C. Normal pressure hydrocephalu, D. Pelizaeus-merzbacher disease', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Normal pressure hydrocephalus triad:\n\nDementia\nAtaxia\nIncontinence\n\nCT or MRI brain in these patients shows enlarged frontal and temporal horns of lateral ventricles out of proportion to degree of cortical atrophy.', 'role': 'assistant'}]