This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Organic Mental Disorders, Subject name: Psychiatry
[{'content': 'A 52-year-old man with no history of psychiatric illness in past presents with recent onset of disorientation, fluctuating mental status, abnormal autonomic signs, tremor, and seeing "little snakes" in his house. He has no known history of substance abuse. What is the most likely diagnosis? \nSelect and explain. \nA. Schizophrenia, B. Dementia, C. Delirium, D. Depression with psychotic features', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The history is suggestive of sudden onset of disorientation, autonomic instability and hallucinations in a 52 year old person. Most likely diagnosis is delirium.', 'role': 'assistant'}]