In an experiment, which variable is observed and measured to assess the effect?

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

Answer: (B)

The variable you observe and measure to see the result of changing something is the dependent variable. In an experiment, you deliberately change the independent variable to see how it affects the outcome, and the dependent variable is what you record to assess that effect. Control variables are kept constant so they don’t influence the outcome, and confounding variables are extra factors that could skew the results if not accounted for. For example, if you test how fertilizer quantity affects plant growth, fertilizer amount is the independent variable, plant growth (like height) is the dependent variable, soil type and light are control variables, and any unmeasured factor that could influence growth would be a confounding variable.