Answer:
Option (c) ''They are valid because the dependent variable caused a change in the independent variable'' is the correct answer.
Step-by-step explanation:
The dependent variable is the one which is the center of observation. It is changed during the reaction and affected by it. When we measure the value of the reaction we always measure the dependent variable.
The independent variable is the one that is changed to cause the change in the value of the dependent variable. We can say that the dependent variable depends on independent for its reaction.
So dependent and independent variables are correlated with each other which tells the authenticity of the experiment.