Ill say B poor soil Because how would you grown vegetation with out good soil
Answer:
The main factor that causes vasoconstriction is the high concentration calcium inside muscle cells.
Explanation:
When the vessels suffer vasoconstriction, the blood supply is decreased and in this way the heat of the body is maintained. The way this happens is because the blood can no longer reach the surface and therefore decreases outward heat radiation. The main factor that causes vasoconstriction is the high concentration calcium inside muscle cells. There are several factors that cause vasoconstriction, internal or external. Environment is one of the external factors, and what happens to the penguins' feet is an example for it, since they are trying to preserve body heat to survive.