Why do people with Parkinson's disease experience resting tremors?
A. Damage to the cerebellum alternately activates agonist/antagonist muscle pairs.
B. Acetylcholinesterase at neuromuscular junctions is inactivated.
C. Activation of the sensorimotor cortex is reduced when the substantia nigra fails to deliver dopamine to the basal nuclei.
D. Excess glutamate is released in the premotor areas of the motor cortex.
E. Dopamine-secreting tumors directly activate alpha motor neurons.
Answer: C
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