Multiple choice Which of the four are collectively known as brain stem? Pons varolii, mid brain, medulla oblongata and diencephalon Pons varolli, mid brain, cerebellum and thalamus Medulla oblongata, cerebellum, pons varolii and cerebrum Hypothalamus, thalamus, mid brain and cerebellum Reveal answer Fill a bubble to check yourself A Correct answer Explanation This option is correct because they all perform the major function of brain considered as brain stem.