Huntington's disease is characterized by which involuntary movement?

Huntington's disease is primarily characterized by chorea, which refers to the involuntary, unpredictable, and often non-repetitive movements associated with the condition. Chorea results from neurodegeneration in specific areas of the brain, particularly the basal ganglia. This neurodegeneration leads to difficulties in controlling movements, causing patients to exhibit jerky, dance-like motions.

The hallmark of chorea in Huntington's patients distinguishes it from other types of involuntary movements. For instance, tremors are typically more rhythmic and can occur at rest or during activity, while ataxia involves uncoordinated movements and balance issues without the erratic nature of chorea. Spasticity, characterized by increased muscle tone and stiffness, does not represent the involuntary movements seen in Huntington's disease. Therefore, the correct choice emphasizes the specific type of involuntary movement that defines the motor symptoms of Huntington's disease, making chorea the correct answer.