Why is the optic disc sometimes called the blind spot of the eye?

A)There are no rods and cones there.
B)There are no nerve fibers there.
C)There are no blood vessels there.
D)There are rods there, but no cones, so color vision is not possible in that area.
E)There are cones there, but no rods, so black and white vision is not possible in that area.