Answer:
Cotton balls, soil and gravel
Step-by-step explanation:
The independent variable in an experiment is the variable that is exposed to the change or which undergoes changes as per the experimenter. The changes are brought in order to calculate the significant change in the dependent variable.
In the experiment conducted by Janessa, cotton balls, soil and gravel are the independent variables that are induced by her. The dependent variable in this experiment is the measurement and recording of the growth of the plant. She conducted the experiment to calculate as to which material would be best suited for the lima beans to sprout.