Which sentence contains an antecedent that is unclear, missing, or confusing?

A.
When you and your friends hear this African music, you'll love it.

B.
On the sheet handed out at the first meeting, our responsibilities were clearly outlined.

C.
Aunt Ellie and I love quilting, but she prefers to use a machine instead of a needle.

D.
I tried to interest the newspaper in the issue, but they weren't interested.