A group of researchers conducts a study on aggression. They randomly assign a sample of ten-year-olds to view either an aggressive video or a nonaggressive video, and then they measure the amount of aggressive behavior the children exhibit. The researchers are using the type of video watched (aggressive or nonaggressive) as which of the following types of variables?

A confounding variable is an external influence that can affect the outcome of an experiment but is not the variable being tested. In this study, the type of video is not confounding; instead, it is the primary independent variable being manipulated to observe its impact on aggression.

Control variables are those that researchers keep constant to ensure that any observed effects can be attributed to the independent variable. While the study may have control variables, the type of video being shown is not one of them; it is the independent variable being tested.

Intervening variables are those that mediate the relationship between the independent and dependent variables. In this scenario, the type of video viewed does not act as an intervening variable but rather as the independent variable itself.

The dependent variable is the outcome measured in the experiment, which in this case is the aggressive behavior exhibited by the children. The type of video is not dependent on anything but is instead the factor that is altered to observe its effects.