Answer:
D. Control the blood flow into the capillary bed
Explanation:
The degree of filling of the capillary bed and level of arterial pressure within the vascular system is determined mainly by the degree of tonus (firmness) in the smooth muscle of the arterial wall. Arterioles have relatively narrow lumina, thick muscular wall and precapillary sphincter.
D, it is only dominant because it stands out more not because it is better
A country that is not growing is characterized by an age structure that is largest among post-reproductive years.