What are the two main components of the nervous system?

The two main components of the nervous system are the Central Nervous System (CNS) and the Peripheral Nervous System (PNS). The CNS includes the brain and spinal cord, which serve as the primary control center for processing information and coordinating responses. It is responsible for higher-level functions such as thought, memory, and voluntary movement. The PNS, on the other hand, encompasses all the neural pathways outside the CNS. It connects the CNS to the rest of the body, including organs, limbs, and skin. The PNS is further divided into the somatic nervous system, which controls voluntary movements, and the autonomic nervous system, which regulates involuntary functions like heart rate and digestion.

While the other options mention components of the nervous system, they do not accurately capture its two principal divisions. The autonomic nervous system and somatic nervous system are subdivisions of the PNS, and thus do not represent the complete structure of the nervous system as a whole. Therefore, the classification into CNS and PNS provides a clearer understanding of how the nervous system is organized and operates.