Here are the closest meanings for each question:

17. They raise cows, buffaloes for their own use.
- **D. cattle** (because cows and buffaloes are both types of cattle).

18. The Muong in Hoa Binh and Thanh Hoa are well-known for their rich folk literature and their traditional songs.
- **A. famous** (as it directly matches the meaning of "well-known").