To test how fertilizer affects tomato plants, a farmer divided a field of young tomato plants into 10 plots of equal size. The farmer then put fertilizer on half of the plots and no fertilizer on the other half of the plots. What is the control group in this experiment?
The control is the group of no fertilizers. A control in an experiment is usually the group without the variable to be tested. In this case, the farmer wanted to test the effects of fertilizers, therofre the group without it is the control group.