Final answer:
After the Second World War, the federal government of the United States grew larger and more powerful, contrary to the belief that it became smaller.
Step-by-step explanation:
The federal government of the United States changed after the Second World War due to the global burdens assumed by the country. Contrary to option (a), the government did not become smaller. Instead, it grew larger and more powerful, as described in option (e). The federal government took on new responsibilities and expanded its control, particularly through the military-industrial complex and the efforts of both major political parties and lobbying.
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