Beth presented the following argument: it is hard to deny that humans need sleep. our brains and bodies need it to function properly. our relationships function better, too, when we're properly rested. a teenager's internal clock, however, seems to differ from that of the rest of the population. our bodies tell us to go to bed later, which means we need to get up later, too. therefore, middle and high schools should start classes no earlier than noon. what kind of writing style does beth use for her argument, and how do you know? a. a formal writing style; she includes a claim and supporting reasons. b. an informal writing style; her audience is people younger than she is. c. a formal writing style; she uses few contractions, no slang, and correct grammar. d. an informal writing style; she includes contractions, slang, and incorrect grammar.