Which system includes cranial and spinal nerves?

The correct choice encompasses the network of nerves that lie outside the brain and spinal cord, specifically the cranial and spinal nerves. This system is essential for connecting the central nervous system with limbs and organs, enabling communication between the brain and the rest of the body. The cranial nerves emerge directly from the brain, while the spinal nerves arise from the spinal cord, facilitating motor and sensory pathways.

The central nervous system, on the other hand, consists solely of the brain and spinal cord and does not include any peripheral nerves. The enteric nervous system specifically governs the gastrointestinal tract and functions independently of the other systems. Lastly, the somatic nervous system refers to the part of the peripheral nervous system that controls voluntary movements through skeletal muscles, thus representing only a portion of the broader peripheral nervous system. Therefore, the extensive involvement of both cranial and spinal nerves confirms that the peripheral nervous system is the correct answer.