Which statement best describes the meninges?

• A. Cerebrospinal fluid producing ventricles
• B. Pia mater, arachnoid mater, dura mater
• C. Myelin sheaths around nerves
• D. Neuronal cell bodies in the CNS

Answer: (B)

The meninges are the protective membranes that surround the brain and spinal cord, made up of three layers: dura mater on the outside, arachnoid mater in the middle, and pia mater closest to the brain. This description names all three layers, which is exactly what the meninges are. The dura is the tough outer layer, the arachnoid is a loose, web-like middle layer that helps cover the CNS and, with the pia, helps enclose the subarachnoid space where cerebrospinal fluid flows, and the pia mater tightly adheres to the brain’s surface. Together, they shield the CNS and provide structural support and containment for CSF.

Other options point to different parts of the nervous system: ventricles produce cerebrospinal fluid and are internal brain cavities, myelin sheaths wrap axons to speed impulses, and neuronal cell bodies reside in grey matter, not the protective membranes.