A 67-year-old man presents with progressive tremor. Vital signs: BP 138/82, HR 78, RR 16, temp 37.2°C, SpO2 98%. On examination, he demonstrates a 4-Hz rhythmic pill-rolling tremor of both hands at rest that diminishes with intentional movement. Gait is normal and strength is intact. MRI brain shows no acute findings. He denies recent medication changes and takes only lisinopril. Which neuroanatomic lesion most likely accounts for his resting tremor that improves with purposeful action?

1. A)Demyelination of the dorsal columns
2. B)Degeneration of dopaminergic neurons in the substantia nigra pars compactaGABARITO
3. C)Infarction of the subthalamic nucleus
4. D)Lesion of the cerebellar hemispheres
5. E)Destruction of the caudate nucleus