Select three things an author may use to describe his characters.

antagonist
physical features
protagonist
conduct
conversation

Antagonist, Protagonist, and Physical Features.

Explanation:

This is because these words WERE meant for helping characterization. For example, you could say that the Villain is the antagonist: because they are against the Hero (also known as the protagonist). Physical Features can be used to help describe characters traits that helps you picture their looks. For example: Bobby is a short boy with brown hair. He has brown eyes like his father. Hope this helps!

explanation: the line "to save the day, harry must get past a scary three-headed guard dog" from the summary best justifies the conclusion that harry potter and the sorcerer’s stone was influenced by ancient greek mythological literature. the three other choices had nothing to do with ancient greek literature - and the words "three-headed guard dog" are what makes that choice the correct answer.