Which option would allow Stella to set up a control group for the experiment?
A
She should give the plants receiving the least cap c cap o sub 2 a little more oxygen to compensate for the difference in gases.B
She should provide mist to each of the plants except one plant to keep the air moist and fertilize the plants.C
She should give all the flowers the same amount of water.D
She should place one flower in a similar container, but not pump carbon dioxide into it.