题目

Daily overuse of media and technology has a bad effect on the health of all children and teenagers by making them more open to anxiety, and more at risk of future health problems.【1】 Many newer apps automatically show where the users are when they’re used. This can tell anyone out there exactly where to find the person using the app.【2】 They are also upset about their kids spending time on Facebook accounts instead of getting down to their homework assignments, and are afraid of what can come out of their online connections.【3】 One way is to make a “social media agreement” wi（2010?常德）下列物质属于合金的是（　　）A．赤铁矿B．生铁C．氧化铝D．金刚石