Which of the following regions of the brain is the largest? A. hindbrain B. midbrain C. forebrain

C is the correct answer. The forebrain is the largest region of the brain, accounting for around two thirds of the brain's mass. It contains the cerebrum, olfactory and optic cranial nerves, frontal, parietal, occipital and temporal lobes, and the thalamus, hypothalamus and pituitary gland.