If epinephrine is injected into the cardiovascular system, it will:

When epinephrine is injected into the cardiovascular system, it stimulates the adrenergic receptors, which leads to several physiological effects. One of the primary actions of epinephrine is its ability to increase heart rate and enhance the force of cardiac contraction. This results in a higher cardiac output, which elevates blood pressure.

In addition to this, epinephrine causes vasoconstriction in some vascular beds due to stimulation of alpha-adrenergic receptors, further contributing to the rise in blood pressure. While it can also induce vasodilation in certain areas (such as the skeletal muscles) through beta-adrenergic receptors, the overall effect in a systemic response typically favors an elevation in blood pressure.

This is why the correct answer indicates that epinephrine will increase blood pressure when injected into the cardiovascular system.