Jane: Television programs and movies that depict violence among teenagers are extremely popular. Given how influential these media are, we have good reason to believe that these depictions cause young people to engage in violent behavior. Hence, depictions of violence among teenagers should be prohibited from movies and television programs, if only in those programs and movies promoted to young audiences.
Maurice: But you are recommending nothing short of censorship! Besides which, your claim that television and movie depictions of violence cause violence is mistaken: violence among young people predates movies and television by centuries.
Which one of the following, if true, most strengthens Jane's argument?