ACAP 4th Grade Science Practice Test

Focus on what you are measuring to see the result of your experiment. The dependent variable is the part you observe or measure to find out how the change you made affects it. You purposely change one factor—the independent variable—and watch how the dependent variable responds. The dependent variable depends on that change, which is why measuring it reveals the outcome. The constant factor stays the same to prevent other things from influencing the result, and the hypothesis is a prediction about what you think will happen. So, the description that identifies the variable as the one measured or observed is the best match.