Explanation

A-Forebrain, B-Brain stem C-Corpus callosum, D-Cerebral aqueduct. Forebrain consists of cerebrum, thalamus and hypothalamus. The medulla pons, midbrain and diencephalon are collectively called the brain stem. Cerebrum is divided longitudinally into the left and right cerebral hemisphere. The hemispheres are connected by a tract of nerve fibres called corpus callosum. Cerebral aqueduct is a canal that passes through the midbrain