Final answer:
The United States emerged as the most powerful nation after World War II due to its monopoly on atomic weapons and expanded production capacity.
Step-by-step explanation:
The United States emerged from World War II as the most powerful nation due to a combination of factors. Firstly, option a) is correct. The United States had a monopoly on atomic weapons, which gave them a significant advantage over other nations. Additionally, the country's expanded production capacity allowed it to rebuild and grow its economy rapidly after the war.
However, it is important to note that option b) and option c) are not accurate. While the United States' role in the war certainly had an impact on its international standing, other nations did not simply submit to American authority. The United States emerged as a superpower because of its military and economic strength, not solely because of its heroic role in the war or the support of its public.
Option d) is also incorrect. While government economists did play a role in planning for the postwar economic downturn, it was not the primary factor behind the United States' emergence as the most powerful nation in the world.
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