Without being able to see the diagram you're referring to, I can provide information based on common brain anatomy.
- Cerebellum: Located at the back of the brain, responsible for coordination and balance.
- Corpus Callosum: The structure that connects the left and right hemispheres of the brain.
- Midbrain: Part of the brainstem involved in vision, hearing, and motor control.
- Pons: Also part of the brainstem, it acts as a bridge between various parts of the nervous system and is involved in regulating sleep, respiration, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expressions, and facial sensations.
If part D corresponds to one of these structures, you would need to compare the description of part D in the diagram to these descriptions to determine which part it is. If you can provide details about part D's location or characteristics, I can help you narrow it down further!