I think C. will be the right choice!
The United States was alarmed by Soviet control of Eastern Europe at the end WW II because officials believed Soviet expansion would not stop at Eastern Europe.
<u>Explanation:</u>
The Grand Alliance, otherwise called The Big Three, was a military union comprising of the three significant Allies of World War II: the Soviet Union, the United States, and the United Kingdom. Relations between the Soviet Union and the United States were driven by a perplexing exchange of ideological, political, and monetary elements, which prompted moves between wary collaboration and frequently severe superpower contention throughout the years.
The war changed the economical balance of the world, leaving European countries deep in debt and making the U.S. the leading industrial power and creditor in the world.
The First World War destroyed empires, created numerous new nation-states, encouraged independence movements in Europe’s colonies, forced the United States to become a world power and led directly to Soviet communism and the rise of Hitler. Diplomatic alliances and promises made during the First World War, especially in the Middle East, also came back to haunt Europeans a century later. The balance of power approach to international relations was broken but not shattered. It took the Second World War to bring about sufficient political forces to embark on a revolutionary new approach to inter-state relations.
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