Which of the following best describes the protection role of the CNS encasing?

• A. Electrical insulation
• B. Mobility support
• C. Protection
• D. Nutrient storage

Answer: (C)

The protective encasing around the CNS is all about shielding delicate neural tissue. The skull and the vertebral column form a hard, protective armor, while the meninges—three protective membranes—lie inside that bony shell to cushion and anchor the brain and spinal cord. Cerebrospinal fluid adds a further protective layer by acting as a cushion and helping maintain a stable environment. This combination primarily guards the CNS from physical injury, infection, and chemical fluctuations, keeping the neural tissue safe and functioning smoothly.

Electrical insulation, by contrast, comes from myelin sheaths around nerve fibers, not from the CNS’s encasing as a whole. Mobility support is the role of the skeletal system and joints, and nutrient storage is not a function of the CNS’s protective encasing.