Guillain-Barre Syndrome features immune system attacks the peripheral nervous system.

• A. Progressive brain degeneration
• B. Immune system attacks the peripheral nervous system
• C. Brain tumor
• D. Inflammation of meninges

Answer: (B)

Guillain-Barré Syndrome is defined by an immune-mediated attack on the peripheral nervous system. In this condition, the body's immune response mistakenly targets the nerves outside the brain and spinal cord, often damaging the myelin sheath or the nerve fibers themselves. This leads to rapid-onset weakness that commonly starts in the legs and moves upward, along with reduced or absent reflexes, and can progress to involve the respiratory muscles.

This choice is the best because it matches the actual site and mechanism of pathology in Guillain-Barré Syndrome—peripheral nerves affected by immune activity—rather than structures within the brain or its coverings. In contrast, progressive brain degeneration would involve the brain itself, not the peripheral nerves. A brain tumor is a growth inside the brain, again central rather than peripheral nervous tissue. Inflammation of the meninges refers to meningitis, which affects the protective coverings of the brain and spinal cord, not the peripheral nerves.