In an experiment, which variable is the outcome that you measure?

In an experiment, which variable is the outcome that you measure?

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

Answer: (B)

The outcome you measure in an experiment is the dependent variable. You deliberately change one thing—the independent variable—to see how it affects the dependent variable. For example, if you test how the amount of fertilizer affects plant growth, the fertilizer amount is the independent variable, and the plant height is the dependent variable—the measurement that shows the result. Other factors you keep the same across trials are control variables, which help ensure that any change in the dependent variable is due to the independent variable. The idea of a constant variable isn’t the outcome you observe; it’s about what you keep unchanged. So, the dependent variable is the measurement that reflects the effect of your manipulation.