Answer: Letter “C”, aka “Power shifted from Western Europe to the United States and the Soviet Union.”
Explanation: Before WWI, the centers of world domination were the empires and powers of Western Europe, mainly the British Empire and the Prussian Empire, with the presence of other imperial powers like Russia, the Austria-Hungary Empire, and the Ottoman Empire. All of these empires collapsed at the end of WWI, which caused a big political and ideological crisis in Europe that paved the way for the rise of extremist ideologies like Fascism, Nazism, and Communism. This new setting generated a new clash of imperialism in WWII, in which Nazism and Fascism were defeated and the clear winners of this war were the United States and the Soviet Union. These new global powers that rose from the WWII started a new war between them for world domination: the Cold War, a clash between the Western, democratic, and capitalist world and the Eastern, Soviet, and Communist world.
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