Final answer:
(a) Lithuania, (c) Latvia, and (d) Estonia became independent from the Soviet Union as communism started crumbling in Eastern Europe.
Step-by-step explanation:
The countries that became independent from the Soviet Union as communism started crumbling in Eastern Europe are Lithuania, Latvia, and Estonia.
In 1991, these three Baltic states received their independence from the Soviet Union. They transitioned to market economies with democratic governments and looked towards Western Europe for trade and development.
It is important to note that Finland was not part of the Soviet Union and therefore did not become independent from it.