Which of the following describes the dependent variable in an experiment?

The dependent variable in an experiment refers to the outcome that researchers measure to evaluate the effects of an independent variable, which is the factor being manipulated. This variable changes in response to the manipulation, allowing researchers to observe if there is a significant effect. It essentially provides the data needed to determine whether the hypothesis has been supported or refuted. For instance, if a study is exploring the impact of a new teaching method on student performance, the students' scores would be considered the dependent variable. By focusing on this outcome, researchers can assess how the manipulation affects the results, making it integral to the experimental process.

The other choices do not accurately define the dependent variable. Not measuring the dependent variable at all would eliminate the ability to evaluate the outcomes of the experiment. The initial conditions refer to what is known as the baseline or control factors prior to any manipulation, and the selection process of participants is unrelated to the variable measured.