Which component of the nervous system contains the brain and spinal cord?

The central nervous system is the correct choice because it encompasses the brain and spinal cord, which serve as the main control center for processing information in the body. The brain is responsible for higher cognitive functions, sensory processing, and coordinating movements, while the spinal cord acts as a communication conduit between the brain and the rest of the body, relaying signals to and from peripheral nerves.

In contrast, the main nervous system is not a recognized term in neurology, making it an invalid choice. The peripheral nervous system, which includes all the nerves outside the brain and spinal cord, functions to connect the central nervous system with the limbs and organs, thus facilitating communication but does not include the brain or spinal cord themselves. The autonomic system, part of the peripheral nervous system, specifically regulates involuntary bodily functions, such as heart rate and digestion, but again, it does not encompass the brain or spinal cord. Hence, the central nervous system is the definitive answer, as it directly pertains to the structural components mentioned in the question.