Which structures make up the central nervous system (CNS)?

• A. Cranial nerves and spinal nerves
• B. Brain and spinal cord
• C. Autonomic ganglia and enteric plexuses
• D. Brain and peripheral nerves

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the definition of the central nervous system (CNS). The CNS consists of the main control centers of the nervous system responsible for processing and integrating information.
2. Step 2: Recall that the CNS is composed of two primary structures: the brain and the spinal cord. These structures are enclosed within the skull and vertebral column, respectively.
3. Step 3: Differentiate the CNS from the peripheral nervous system (PNS), which includes cranial nerves, spinal nerves, autonomic ganglia, and enteric plexuses. These structures lie outside the brain and spinal cord.
4. Step 4: Recognize that cranial nerves and spinal nerves are part of the PNS because they connect the CNS to limbs and organs, facilitating communication between the CNS and the rest of the body.
5. Step 5: Conclude that the correct answer is the brain and spinal cord, as these are the defining structures of the central nervous system.