During Blood Loss Due to Hemorrhage, Perfusing Pressures Can Be

During blood loss due to hemorrhage, perfusing pressures can be kept near normal until the volume loss overwhelms the system. Why is this so?

A) Arteries constrict, increasing vascular resistance.
B) Arterioles dilate, decreasing vascular capacity.
C) Muscle vessels dilate, increasing vascular capacity.
D) Venules constrict, decreasing vascular capacity.