The fundamental source of instability in the balkans in the 1990s was:

The correct answer is the breakup of Yugoslavia in 1991

Yugoslavia started breaking up because of ethnic and religious tensions in the area. Several parts of the country started seceding from Yugoslavia and declaring independence, and Yugoslavia wanted to keep the borders intact. This led to the majority of 90s being a war era which only ended in 1999 after the bombing.

Your answer is b , public works