In an experiment, which variable is measured to assess the effect of the independent variable?

• A. Independent variable
• B. Control variable
• C. Confounding variable
• D. Dependent variable

Answer: (D)

The variable you measure to see how the independent variable affects things is called the dependent variable. It’s the outcome or response that can change in relation to how you manipulate the independent variable, so it tells you whether the change you introduced had an effect. For example, if you change the amount of fertilizer (independent variable) and observe how tall the plants grow, plant height is the dependent variable because it depends on the fertilizer level. Control variables are kept the same to isolate the effect, and a confounding variable is an outside factor that could also influence the outcome, potentially obscuring the true relationship. So the measured outcome used to assess the effect is the dependent variable.