Explanation

A-Brain (encephalon); B-Cranial Nerves; C-Spinal Nerves; D-Spinal cord (myelon) CNS lies along the main (longitudinal) axis of the body. The CNS consists of two parts, i.e., the upper large brain or encephalon, situated in the head and the low long narrow spinal cord or myelon, located in the neck and trunk