B. It allows readers to sympathize with the monster whom Victor describes as a horrible wretch.
Up until this point Victor is the narrator, and because the monster isn't what he envisioned he has painted a negative image of him to the reader. This chapter creates depth to the monster and builds character. Reading what he experienced through his eyes is meant to make the reader sympathetic to him.
While there is significant foreshadowing to justify C being the answer, I believe that allowing the reader to sympathize with the monster has a bigger impact in this chapter and overall story.
