Which nervous system regulates involuntary body functions such as heart rate and digestion?

• A. Central nervous system
• B. Autonomic nervous system
• C. Somatic nervous system
• D. Peripheral nervous system

Answer: (B)

The function being tested is which part of the nervous system handles automatic, involuntary body operations like heart rate and digestion. The autonomic nervous system does this work without conscious effort, regulating internal organs through its sympathetic and parasympathetic branches. For example, it can quicken the heartbeat in response to stress or slow digestion when resting.

The other systems don’t fit as well: the central nervous system processes and integrates information but doesn’t directly drive involuntary organ activity; the somatic nervous system controls voluntary muscle movements; and the peripheral nervous system includes many nerves outside the CNS but doesn’t specify the automatic regulation of internal functions.