Hi! I'm super sorry that I can't help. I've never read the passage
I think it might be “It introduces the story and sets up the coming events.” I’m not sure so take this with a grain of salt...
Based on my prior knowledge of the word I would say C (unoriginal) is a pretty safe choice.
It depends on your learning type (kinetic, visual, auditory, etc.) however most evidence proves that A.) quizzing yourself would be the best answer