8. Scientists suspected that fertilizers applied to farm lands also contaminated groundwater, which in turn increased nutrient input into the lake. In order to best test this hypothesis, which of the following should the scientists do next?
Your Answer is
Correct Answer is J
Explanation
The question stem requires to study the pollution of lake water by using chemical fertilizers, so the independent variable (fertilizer, different dosage) and dependent variable (groundwater flowing into the lake) need to be set in the design laboratory