Why was there tension between the US and the USSR after World War II?

It´s C) Their economies were based on different principles and systems .

In the first place, the tensions evolved around the question of what to do with Germany. The Soviet Union opposed reviving a strong German state, out of its own security concerns. When the US and the Western allies agreed to create the Federal Republic of Germany, Joseph Stalin replied by creating a communist state, the German Democratic Republic. Other important source of tensions was the economic recovery of Europe; Washington feared that poverty and economic ruin could help a communist expansion. Besides, there were Soviet troops in the territory of Eastern European nations, and there, the USSR played a hand in installing communist leaders. And both powers represented opposed ideologies and political systems: democracy and free-markets versus state economy and totalitarian one-party rule.

Explanation:

c.) biotic: snails; abiotic: temperature climate

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