Which progressive brain disease is described as the most common form of dementia, affecting memory, thinking, and behavior, with no known cure?

• A. Parkinson's Disease
• B. Alzheimer's Disease
• C. Huntington's Disease
• D. Multiple Sclerosis

Answer: (B)

Alzheimer's disease is the progressive brain disorder described here. It is the most common cause of dementia, and it gradually erodes memory, thinking, and behavior, which interferes with daily life. There is no cure at present, though treatments can help manage symptoms and may modestly slow decline for some people. This set of features—progressive cognitive decline with no currently available cure—fits Alzheimer's best, whereas the other options involve different primary problems (Parkinson's with movement issues, Huntington's with genetic neurodegeneration affecting movement and cognition, and multiple sclerosis with demyelination and a broader range of neurological symptoms).