Ascientist wants to determine which fertilizer is more effective—fertilizer x or fertilizer y.
the best way for her to proceed would be to design an experiment with
a.
three groups of plants—a group fertilized by x, a group fertilized by y, and a control
group with no fertilizer.
b. two groups of plants—a group fertilized by x and a control group with no fertilizer.
c. two groups of plants—a group fertilized by y and a control group with no fertilizer.