Pick more than one. Which sentences contain an adverb clause? -Darla set up a studio because she enjoyed painting.
-As Aaron was having a midnight snack, he heard a loud noise coming from the basement.
-The entire town was searching for the girl with the red hair.
-They listened to what he had to say but disagreed with him in the end.

a.) it provides a clue to solve the mystery.

the pronoun reference replaces a noun, but you have to make sure there's no room for confusion.

in the first sentence "her" could be referring to shely or to the sister. the answer there is "shelly called her sister and told her about the new baby."

in the second sentence "it" could be referring to the roof or the floor. the answer there is "since the roof leaks on the family room floor, we need to repair the roof."