When You Stand Up Suddenly, What Happens Initially to the Blood

When you stand up suddenly, what happens initially to the blood pressure at the carotid sinus, prior to any compensation?

A) It decreases by approximately Dgh where h is the distance between aorta and carotid sinus
B) Nothing happens to it because the carotid sinus is at the center of gravity of the circulatory system
C) Nothing happens to it because the heart rate increases to adjust the pressure
D) Nothing happens to it because the heart rate decreases to adjust the pressure
E) Nothing happens to it because the stroke volume increases to adjust the pressure