Attaching audio to cloze deletion

Hello Everyone,
My version is 2.1 on a MacBook.
What is the best way to attach mp3’s to each individual answer {{c1}}, {{c2}}, and so forth? I am working with learning-disabled children, and it would be nice to give them a sound hint every time they hit a clozed word. No matter what I do, the word is repeated throughout the whole passage, not matching specific closeouts.
Thank you,