Question

which term best describes the soviet states transition into independence?
violent
challenging
lengthy
smooth

Explanation:

While some Soviet states faced localized conflict, the overall collapse of the USSR and most states' independence was relatively unmarked by large-scale, prolonged war. The transition was not overly lengthy, as most republics declared independence in 1990-1991. "Challenging" is too vague, and the majority of the 15 Soviet republics achieved independence with minimal large-scale violence, making "smooth" the most accurate broad descriptor of the overall transition.

Answer:

smooth