The sympathetic and parasympathetic nervous systems are two divisions of the ______.

• A. Somatic nervous system
• B. Sensory system
• C. Brain
• D. Autonomic nervous system

Answer: (D)

The autonomic nervous system governs involuntary bodily functions and has two main branches: the sympathetic and the parasympathetic systems. The sympathetic branch prepares the body for action, increasing heart rate, dilating airways, and releasing stored energy during “fight or flight.” The parasympathetic branch promotes rest and recovery, slowing the heart rate and stimulating digestion to conserve and restore energy. Together, they balance how our organs operate without conscious effort, maintaining homeostasis.

The other options don’t fit because the somatic nervous system handles voluntary control of skeletal muscles, not automatic internal regulation; the sensory system deals with sensing and sending information about the environment to the brain; and the brain is an organ, not a division within the nervous system.