There were some other interesting findings in the report. For instance, the least happy adolescents used screens for twenty hours or more a week. However, adolescents who had between one and five hours of screen time a week were happier than those who didn’t have any. This excerpt would be most useful for a research paper on which topic?

A. the uses of smartphones

B. the future of smartphones

C. the benefits of smartphones

D. the convenience of smartphones