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': 'Features of parkinsons disease-a) Decreased Blinkingb) Spasticityc) On-off phenomenond) Objective ↓ muscle powere) Tremor \nSelect and explain. \nA. acd, B. bde, C. cde, D. ace', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]