Cite a particular piece of evidence to support the sentence
Input: Violent video games have been proven to increase aggressive behavior
The U.S. Department of Defense conducted a study in which it was found that pupils exposed to violent video games displayed an increased level of aggression compared to pupils who were not exposed to such games. (source: http://www.usairforce.com/content/usaf/news-and-explore/cia/violent-video-games-increase-aggression-in-teenagers.backend.render.html)
Violent video games have been proven to increase aggressive behavior (Ferguson, 2015).