A 71-year-old woman with Parkinson disease treated with levodopa for 8 years presents with repetitive involuntary writhing and choreiform movements beginning 30 minutes after each dose. Vital signs: BP 138/82, HR 92, RR 16, Temp 37°C, SpO2 98%. Brain MRI shows no structural abnormalities. Her bradykinesia improves with medication, but tremor persists. She denies hallucinations. Which of the following best explains these new involuntary movements?

1. A)Progression to Huntington disease
2. B)Acute dystonic reaction from dopamine antagonism
3. C)Essential tremor unmasked by beta-blocker withdrawal
4. D)Levodopa-induced dyskinesia from pulsatile dopaminergic stimulationGABARITO
5. E)Cerebellar degeneration from alcohol use