What does the author mean by saying, "As I sat up, the mattress springs hummed a squeaky tune"?
A.
Charlie hears a squeaking sound coming from the bed's springs as he gets up.
B.
Charlie rolls over in bed which causes the mattress springs to squeak.
C.
Charlie's bed makes squeaky music by using the mattress springs as an instrument.
D.
Charlie's mattress lets out a humming sound that causes him to wake up early.