What is the difference between an independent variable and a dependent variable?

The distinction between an independent variable and a dependent variable is fundamental in psychological research and experimental design. The independent variable is the factor that the researcher manipulates or changes to observe its effect. In contrast, the dependent variable is the outcome or response that is measured to see if it changes as a result of the manipulation of the independent variable.

In this context, option B accurately describes this relationship by stating that the dependent variable is the measure of the outcome while the independent variable is manipulated. This reflects the goal of experiments, which is to assess how variations in the independent variable lead to changes in the dependent variable, thus allowing researchers to establish cause-and-effect relationships.