Underline the adjetives in the sentences

the answer is: apostrophe and allusion.

apostrophe refers to a poetic technique that is used to address an absent individual or an abstract idea/being. allusion on the other hand is a poetic technique that being done by making an indirect reference to other person with a high level of significance (could be historically or culturally significant)

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.