Which of the following is classified as a progressive disease of the CNS?

The correct answer, Huntington's disease, is classified as a progressive disease of the central nervous system (CNS) because it involves a gradual degeneration of neurons, particularly in the basal ganglia and cortical areas of the brain. This progressive deterioration leads to a range of cognitive, motor, and psychiatric symptoms, which worsen over time. As the disease advances, individuals typically experience increasing difficulty with movement, changes in behavior, and cognitive decline, ultimately impacting daily functioning and quality of life.

In contrast, multiple sclerosis is considered a demyelinating disease characterized by relapses and remissions rather than a linear progressive decline in function. Epilepsy is not classified as progressive; instead, it is a seizure disorder that can be episodic in nature, with the severity and frequency of seizures varying widely among individuals. Traumatic brain injury is an acute event that can lead to a range of impairments but does not inherently involve a progressive disease course like Huntington's disease does.