Which of the following is NOT a primary symptom of Parkinson's disease?

The correct choice identifies drooling as not a primary symptom of Parkinson's disease, distinguishing it from the other options which are recognized as core motor symptoms of the condition.

Bradykinesia refers to the slowness of movement, which is one of the cardinal symptoms of Parkinson's disease. It significantly impacts the individual’s ability to initiate and perform voluntary movements, contributing greatly to the overall functional decline associated with the disease.

Postural instability involves issues with balance and coordination, leading to a higher risk of falls. This symptom becomes more pronounced as the disease progresses and is a key factor in managing the health and safety of individuals with Parkinson's.

Rigidity refers to the stiffness of the muscles, which can affect the limbs and trunk, contributing to reduced mobility and discomfort. This symptom often coexists with the other primary motor symptoms and can lead to secondary complications due to decreased physical activity.

Drooling, while it can occur in individuals with Parkinson's disease due to muscular control issues and motor function decline, is not classified among the primary symptoms. It is considered more of a secondary symptom related to difficulties with swallowing or reduced saliva control rather than a direct consequence of the hallmarks of Parkinson’s disease. Understanding this distinction is crucial for comprehending the broader spectrum