The Best Evidence for the Perceptual Reality of Color-Grapheme Synesthesia

The best evidence for the perceptual reality of color-grapheme synesthesia is that

A) a synesthete reports that the synesthetic colors add to ink colors.
B) a synesthete reacts more slowly in naming an ink color when the synesthetic color is different from the . color of the ink than a nonsynesthete does.
C) a synesthete identifies a shape when the elements and background are different synesthetic colors faster than a nonsynesthete does.
D) a synesthete insists on color compatibility of the names of spouses.