Answer:
randomly requiring half the drivers to drive with sunglasses and the other half to drive without sunglasses.
Explanation:
When employing an independent group design in a research or experimental study, the different groups in the study are assigned entirely different subjects such that, subjects in the treatment group are different from those in the control group. Therfore, adopting an independent group design in the scenario described above means diving the subjects into two at random with one half driving with sunglasses and the other half having to drive without it.