Color Blindness is an X-linked trait. This explains why males are much more likely to have it than females. Offspring inherit Color Blindness from their mother, because the father only contributes the Y chromosome. A female can only have the disorder if her father has it and her mother either has it or is a carrier
She could use a control to compare her data to and make sure it is cleaner. Ex. Use the old detergent on ten shirts and then use the new detergent on another ten shirts. She would then compare the shirts she did each detergent on and come up with her conclusion.
I believe the answer is B. Hope I help! Sorry if not. ):)
