Answer:
The correct answer is - the dependent variable.
Step-by-step explanation:
In any study or research, the variable is that measured or affected by the change occurs lace in an experiment is called the dependent variable. The dependent variable depends on the factors or the variables that are changed in the experiment.
In this particular study, the variable which is measure is the height or growth of the plant which depends on the change in the hydrating supply so the dependent variable will be - the growth of the plant.