You perform an experiment in which you take 16 pots of strawberry plants and give half of them 1 gm of ammonium nitrate per liter of water and the other half receive only water. Each group is then split in half again, and exposed to either 8 or 16 hours of light each day. You monitor the height of the plants for 4 weeks. You observe that plants grown in ammonium nitrate and 16 hours of light grow taller than no ammonium nitrate and 8 hours of light. Which of the following are dependent variables in this experiment? A. An independent variable.
B. A dependent variable.
C. A controlled variable.
D. Either an independent or dependent variable.
E. Either a dependent or standardized variable.