Which Region of the Brain is the Smallest and Oldest

Question

Which region of the brain is the smallest and oldest in evolutionary development
A)cerebellum
B)brain stem
C)hypothalamus
D)forebrain

Accepted Answer

The brain stem, which includes structures such as the medulla, pons, and midbrain, is the smallest and oldest part of the brain, responsible for basic functions such as breathing, heart rate, and arousal. It is considered to be the most primitive part of the brain, as it is found in all vertebrates and controls essential bodily functions necessary for survival.