What is the effect of vasoconstriction on blood pressure?

Vasoconstriction refers to the narrowing of blood vessels, which increases the resistance within the circulatory system. When blood vessels constrict, the same volume of blood is forced through a smaller space, leading to an increase in blood pressure. This process is often a physiological response to factors such as stress, cold temperatures, or certain hormones, and it serves to maintain adequate blood pressure during times of need, such as in a fight-or-flight situation.

As a result, when vasoconstriction occurs, it directly contributes to an increase in systemic vascular resistance, which, according to Ohm's Law (blood pressure = cardiac output x systemic vascular resistance), leads to a rise in blood pressure. This is why the correct answer identifies that vasoconstriction results in increased blood pressure.