A student is conducting a research project examining whether a parent’s income impacts a child’s choice of college. The student thinks parents who make little money will have children who attend public schools, and parents who make a lot of money will have children who attend private schools. Which type of variable is “Parents’ Income” in the student’s project?

A measurement variable refers to a variable that can be quantified and measured directly, such as height or weight. While parents' income could be quantified, the term "measurement variable" does not accurately convey the role it plays in influencing the dependent variable (college choice) in this research project.

The dependent variable is the outcome that is measured in an experiment, which in this case is the child's choice of college. Parents' income, however, is not the result of the study but rather the factor that is assumed to influence the outcome, making it incorrect to classify it as a dependent variable.

Control variables are constants that are kept the same throughout an experiment to ensure that the results are due to the manipulation of the independent variable alone. Parents' income is not controlled in this study but is instead varied to see how it impacts the dependent variable, making it unsuitable as a control variable.