The best way to earn good grades is to work hard and study. the underlined phrase is which of the following? (5 points) prepositional gerundial infinitive participial

Which sentence is an example of objective, third-person writing that could be found in a scientific essay? a. i was 15 years old when i developed an eating disorder. b. my sister developed an eating disorder when she was a teenager. c. eating disorders often appear during the teen years. d. you are most likely to develop eating disorders during your teenage years.