Which best describes the brain stem?
a) the brain stem is found in the midbrain
b) the brain stem controls critical thinking
c) the brain stem controls blood circulation
d) the brain stem regulates the release of hormones

C) The brain stem controls blood circulation

Explanation:

The brainstem is the part of the human brain present in the posterior side. It remains in proximity with the spinal cord. A typical brain stem in humans include the midbrain, pons and medulla oblongata present in the hindbrain.  It controls various activities in the central nervous system. These includes consciousness, regulation of blood circulation, and breathing.  

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.