Which statement best describes the central nervous system?

• A. Includes the nerves and sensory receptors
• B. Includes the brain only
• C. Includes the brain and spinal cord
• D. Includes the spinal cord only

Answer: (C)

The central nervous system consists of the brain and spinal cord, where information is processed, integrated, and coordinated. The brain interprets sensory input, thoughts, memory, and actions, while the spinal cord serves as the main pathway for signals traveling between the brain and the rest of the body and handles many reflexes.

Nerves and sensory receptors are part of the peripheral nervous system, which connects the CNS to muscles and organs. If you only consider the brain, you miss the crucial role the spinal cord plays in transmitting information and coordinating responses. If you only consider the spinal cord, you’d omit the brain’s higher-level processing.