Which nervous system controls the function of the diaphragm?

The diaphragm, the primary muscle involved in the process of breathing, is controlled by the somatic nervous system. This part of the nervous system is responsible for voluntary muscle movement, allowing for conscious control over breathing. The diaphragm receives its motor innervation from the phrenic nerve, which is rooted in the cervical spinal cord (C3-C5), emphasizing the somatic nature of this control.

While the autonomic nervous system does regulate involuntary functions such as heart rate and digestion, it does not directly control the diaphragm's muscle contractions. The central nervous system comprises the brain and spinal cord and mediates various functions, but the direct control of the diaphragm is specifically a function of the somatic system. The peripheral nervous system includes both the somatic and autonomic divisions, but it is too broad to specify the control mechanism of the diaphragm accurately.

Therefore, the role of the somatic nervous system in controlling the diaphragm is paramount for both voluntary and, to some extent, involuntary breathing, making it the correct answer.