The midbrain includes the: O A. corpus callosum.
O B. cerebral cortex.
O C. limbic system.
O D. reticular activating system.

The midbrain includes the reticular activating system.

The midbrain (mesencephalon) is a middle region of the brain stem cells and it is the smallest of the three regions. This is the region of motor movement development pertaining to eye movement(visual) and earing processing(auditory).

The corpus callosum is a huge C-shaped bundle of nerve fibers lying underneath the cerebral cortex(forebrain). It runs across the center of the brain, linking the left cerebral hemispheres and right cerebral hemispheres.

The cerebral cortex is the outermost grey matter covering that spans the whole region of the two cerebral hemispheres.

The limbic system is a set of structures found on opposite sides of the thalamus, just under the cerebrum's temporal lobe, mostly in the forebrain.

The reticular activating system is a bundle of nerve cells in the midbrain stem cells that extend to the hypothalamus(anteriorly) to govern behavioral activities and to the thalamus(posteriorly) and directed toward the cortex to activate alertness.

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