In research, which term describes the variable that is intentionally altered to observe effect?

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

Answer: (D)

The variable that you deliberately change to see its effect is the independent variable. In an experiment, you manipulate this variable and then observe how it influences another measure, the dependent variable, which is what you track or record. For example, if you’re studying how fertilizer amount affects plant growth, the amount of fertilizer is the independent variable and plant height is the dependent variable you observe.

Control variables are factors you keep constant so they don’t affect the outcome. A confounding variable is an uncontrolled factor that could confuse the relationship you’re trying to study, making it harder to tell whether changes in the dependent variable are due to the independent variable. This is why the independent variable is the one intentionally altered.