Beer's law problems?

Hey everyone I'm having issues with a problem on my protein concentration lab.
"To test your understanding of the color wheel and Beer's law, use the space below to graph the relationship between concentration and absorbance for three substances: A, which is green, B, which is yellow, and C, which is red, when they are illuminated with green light. Let the x axis of your graph be concentration of the substance (A,B, and C) and the y axis be absorbance."
So I know concentration and absorbance have a linear relationship, but i'm having trouble connecting them to the color of the substances. How would color affect the absorbance and concentration of the substance and how would i go about creating the graph?