Identify the progressive incurable brain disease that can cause stiff muscles, stooped posture, pin rolling and tremors.

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

Answer: (B)

Stiff muscles, a stooped posture, and a resting tremor described as pin rolling are classic signs of Parkinson's disease, a progressive neurodegenerative disorder. In Parkinson's, loss of dopamine-producing neurons in the substantia nigra disrupts movement control within the basal ganglia, leading to rigidity, slowed movement, and tremors that are most noticeable when the limb is at rest. The disease is incurable, though treatments can help manage symptoms and improve function. Other conditions differ in their typical features: Alzheimer's focuses on memory loss, multiple sclerosis presents with varied neurological episodes and sensory/mgress deficits, and Huntington's causes involuntary jerky movements and cognitive changes. The combination of rigidity, stooped posture, and a resting pin-rolling tremor points to Parkinson's disease.