The correct option is D calming down the body.
Autonomic nervous system is composed of two types of nervous system:
- Sympathetic nervous system
- Para-sympathetic nervous system
Both these systems handle opposite function and try to strike a balance in the body.
Para-sympathetic nervous system is a dampening or calming system whereas sympathetic nervous system is a quick response mobilising system. For example, acceleration of heart-beat and stimulation for glucose production are handled by sympathetic system; inhibition of glucose production and decrease in heart-beat are controlled by para-sympathetic nsystem.