Which statement best describes the dependent variable?

• A. It is the variable that is deliberately changed by the experimenter
• B. It is the variable that is measured to assess the effect
• C. It is the variable kept constant
• D. It is the variable used to group data

Answer: (B)

The dependent variable is what you measure to see the effect of the thing you change. When you run an experiment, you deliberately change something—the independent variable—and you observe the outcome by measuring the dependent variable. This measurement shows how the experiment’s manipulation affects the system.

The dependent variable is the outcome you record as data, which may be a height, a score, a concentration, or any result that reflects the effect of the change. The variable kept constant is the control variable, not what you measure for the outcome. The variable used to group data is a grouping factor, not the measurement of the effect.

For example, if you study how sunlight affects plant growth, the amount of sunlight is the independent variable, and the plant height is the dependent variable—the data you measure to assess the effect of sunlight on growth.