The correct option is A Cerebral hemisphere
The cerebrum is the largest part in the human brain and consists of two cerebral hemispheres which in turn have four lobes; frontal lobe, parietal lobe, occipital lobe and temporal lobe. Corpus callosum is a bridge of white matter that connects two cerebral hemispheres. Olfactory lobes are the small bulb-shaped extension of the human brain and are connected with the limbic system. Optic nerve consists of ganglion cell fibres from the innermost layer of the retina and serves to transmit an impulse to the brain. Thus, the Correct answer is B.