Which nerve system controls voluntary muscle actions?

The correct choice is the somatic nervous system, as it is the division of the peripheral nervous system that is responsible for the control of voluntary muscle movements. This system allows individuals to perform conscious movements, such as walking, talking, and any other physical activities that require a deliberate effort. It connects the central nervous system, which includes the brain and spinal cord, to skeletal muscles, ensuring that the signals sent from the brain directly control muscle contraction and motor actions.

In contrast, the sympathetic nervous system is part of the autonomic nervous system, which primarily regulates involuntary functions such as heartbeat, digestion, and the stress response, without conscious thought. The autonomic nervous system as a whole further divides into sympathetic and parasympathetic systems, both of which operate below the level of conscious control. The central nervous system, while crucial for processing and sending out signals to the somatic nervous system, does not itself directly control voluntary action—this is a function of the somatic division.