The nurse is explaining Parkinson disease to the student nurse. Which statement indicates that the student nurse correctly understands the pathophysiology of the disease?

A. Parkinson disease is characterized by dopamine depletion in the substantia nigra of the brain, resulting in a relative excess of acetylcholine. This imbalance causes the motor symptoms associated with the disease. B. This choice misrepresents the issue; the problem lies in dopamine production, not uptake. C. Demyelination is associated with conditions like multiple sclerosis, not Parkinson disease. D. Parkinson disease is associated with dopamine deficiency, not excess, and a relative excess of acetylcholine, not deficiency.