My first guess would be that it is an independent clause. This is just a single statement.
A place where list items are stored to await retrieval by their owners.
Coarse means rude or rough.
Thus the word that is best associated with the word coarse is B. Roughness.
Roughness is somehow similar to coarse, it shows cruelty or rudeness in some actions or words. Other term that can be used to describe it is being impolite.
Answer:
Jaylen found that few students realized bullying was a big problem. Jaylen has made many new friends through his antibullying campaign.