Final answer:
The Progressivism movement expanded the federal government's role in the early 1900s, leading to increased regulation of businesses and more involvement in social welfare issues.
Step-by-step explanation:
Progressivism in the early 1900s significantly affected the role of the federal government. The correct answer to the question is b. It expanded the federal government's role in regulating business and addressing social problems. This expansion can be seen through several key pieces of legislation and reforms that were aimed at tackling the various social and economic challenges of the time. Notably, legislation such as the Sherman and Clayton Acts were passed to regulate trusts and monopolies, while the Meat Inspection Act and the Pure Food and Drug Act were created to ensure consumer safety. The establishment of the Federal Reserve further illustrated the move towards greater federal oversight in stabilizing the banking system. Furthermore, the Progressive movement brought about substantial legislative changes at the national level, highlighting the shift in governmental roles from local to federal efforts in addressing widespread issues.