Which picture illustrates the anaphase stage of mitosis?
a) picture a, where the spindle fibers start to pull away from the center of the cell.
b) picture b, where nuclear membranes form around each set of chromosomes resulting in two nuclei.
c) picture c, where each pair of sister chromatids attaches to a spindle fiber by its centromere.
d) picture d, where chromosomes coil up, nuclear membranes break down, and spindle fiber systems form.