What color will a solution that absorbs all the green, yellow and red light appear?
The simple answer is blue. The more complex answer is that appearance will also depend on the lighting and other viewing conditions. However, simply looking at subtractive color mixing, if you have absorbed all the green light and all the red light, then you are left with blue (generally people divide the yellow into the green and red regions, but since you said that was all absorbed as well, the answer wouldn’t change).
