What variable is manipulated in an experiment?

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

Answer: (A)

In experiments, the factor you deliberately change to see its effect is the independent variable. This is the manipulated variable you adjust to test whether it causes a change in the outcome. The result you measure is the dependent variable. To ensure the changes you observe are due to the manipulation, you keep other factors constant as control variables. A constant is simply something that doesn’t change, which you hold steady in the setup so it won’t influence the results. For example, if you vary the amount of fertilizer to see its effect on plant growth, the fertilizer amount is the independent variable, the plant height is the dependent variable, and light, water, and soil type are kept constant as control variables.