Here are the best answers for each blank:

1. In Viet Nam, the Dan Bau is one of the traditional **C. music** instruments.
2. My hobbies aren't **B. the same** as hers.
3. Chu Van An **A. was** one of the most famous teachers of Viet Nam.
4. Classical music is as interesting **C. as** folk music.
5. Bessi Smith was born **B. in** a poor family.

So the answers are: C, B, A, C, and B.