Answer:
The dependent variable is the level of aggressiveness.
Step-by-step explanation:
This is a case were researchers exposed children to 2 hours of Tv with violence of without violence. The researchers what to know the level of aggressiveness. Analyzing the information you can see that the amount of time (each day per one moth during 2 hours) on the Tv and the violence or not violence exposition are controlled by the researchers so these ones are the independent variables. And the level of aggressiveness is the dependent variable because this one depend on the amount of time and kind of Tv program.