Which of the following would be the most likely reason for the high resistance of capillaries to blood flow?

A) the diameter of capillaries being so small that the white blood cells must squeeze
B) the diameter of capillaries being so small that that the red blood cells must squeeze
C) the diameter of capillaries being so large that the red blood cells must fill it all up
D) the diameter of capillaries being so large that the white blood cells must fill it all up