In which region of the central nervous system does the dorsal structure refer to?

The term "dorsal" refers to the upper or back side of an organism in anatomical terminology. This descriptor is applicable to multiple regions of the central nervous system, including both the brain and the spinal cord.

In relation to the brain, the dorsal structures include areas such as the dorsal part of the midbrain and various cortical regions located on the top part of the brain. Similarly, in the spinal cord, the dorsal aspect refers to the back part, where sensory neurons enter the spinal cord and relay sensory information to the brain.

Therefore, the correct choice encompasses the brain and the spinal cord, confirming that "dorsal" applies to both areas within the central nervous system. This multifaceted applicability of the term to different parts of the CNS is why the option indicating both the brain and spinal cord is accurate.