Final answer:
The intricate fabric of interconnected neural cells described is the cerebral cortex, which makes up the outer part of the cerebral hemispheres.
Step-by-step explanation:
The intricate fabric of interconnected neural cells covering the cerebral hemispheres, which serves as the body's ultimate control and information-processing center, is known as the cerebral cortex. This part of the brain is responsible for various high-level functions such as reasoning, language, sight, touch, and hearing. The cerebral cortex is characterized by folds called gyri and valleys called sulci, giving it a large surface area for the complex processing of information. The correct answer to the given description is D. Cerebral cortex.