Which phrase best describes the primary function of the parasympathetic nervous system?

• A. Rest and digest
• B. Voluntary movement
• C. Fight or flight
• D. Sensory integration

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by understanding the parasympathetic nervous system, which is part of the autonomic nervous system. Its primary role is to regulate involuntary physiological processes, particularly during restful states.
2. Step 2: Compare the functions of the parasympathetic nervous system with the sympathetic nervous system. The sympathetic system is responsible for 'fight or flight' responses, while the parasympathetic system promotes 'rest and digest' activities.
3. Step 3: Analyze the options provided in the question. 'Voluntary movement' is controlled by the somatic nervous system, not the parasympathetic system. 'Fight or flight' is associated with the sympathetic nervous system.
4. Step 4: Evaluate the phrase 'Rest and digest.' This accurately describes the parasympathetic nervous system's role in promoting relaxation, digestion, and energy conservation.
5. Step 5: Conclude that the correct answer is 'Rest and digest,' as it best aligns with the primary function of the parasympathetic nervous system.