Human brain complexity arises from new systems built on top of older ones. the remnants of humanity's most distant past involve components of the

a) amygdala.
b) hippocampus.
c) brainstem.
d) hypothalamus.

The correct answer is:

C) brainstem.

Explanation:

The brainstem consists of the connection between the spinal cord to the brain. It consists of the posterior part of the brain constituting a really small device composed by three different parts which are: the midbrain, the pons and medulla oblongata. The brainstem is a very important part of the brain for the function of the human body since it controls the primordial motor and sensory nerve connected to the face and neck through internal nerves located in the cranium.