Which sentence uses a verb that agrees with its subject?
a.
the snails in the garden moves slowly.
b.
authors of books receives royalties for their work.
c.
the stripes on the american flag are white and red.
d.
a bag of groceries were found outside the store.

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.

i think the answer is c