We cleaned up the creek.

which of the following best elaborates on the example sentence?
a. a dozen people filled 50 trash bags in only two hours.
b. it was the hardest, dirtiest work i've done in a long time.
c. the creek runs through our neighborhood and collects a lot of trash.
d. you wouldn't believe some of the old junk we found.

A because it's much better than all of them.

The main purpose of exposition is to provide background information.

An exposition is where writers put important background information like the character's past, the setting, or past events significant to the story. It also serves as an introduction to the characters and where the problem of the story establishes.