In which of the following ways is region B in the diagram different from region D? Image of the brain provided with regions A-D labeled. Region A references an inferior (lower) portion of the brain near the brain stem. Region B references the medial (middle) superior (up) portion of the brain. Region C references a medial (middle) inferior (down) portion of the brain. Region D references the posterior (back) inferior (down) section of the brain.

Region B, the corpus callosum, separates the brain into two halves while region D, the cerebellum, communicates between the two halves.
Region B, the cerebrum, is one single unit composed of gray matter, while region D, the cerebellum, is divided into two hemispheres.
Region B, the corpus callosum, is composed of several lobes while region D, the cerebellum, only has one lobe.
Region B, the cerebrum, is divided into two hemispheres while region D, the cerebellum, is one single structure.

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