What was the primary aim of the Progressive Era?

The primary aim of the Progressive Era was to address social issues and reform government corruption and inefficiency. This period, which roughly spanned from the 1890s to the 1920s, was characterized by a widespread push for social justice and reform. Reformers aimed to tackle a variety of issues stemming from industrialization and urbanization, including child labor, women's suffrage, workers' rights, and public health.

Progressives sought to eliminate the corruption that plagued government, often associated with political machines, and they advocated for more direct participation in politics through measures like the direct election of senators and initiatives and referendums. This movement was influential in enacting significant legislation aimed at improving public welfare, regulating businesses, and increasing government accountability.

The other options reflect broader or unrelated concepts. The idea of expanding the American frontier pertains to earlier periods of American history and does not capture the essence of the Progressive movement focused on reforming existing societal structures. Promoting isolationism relates more to foreign policy stances that developed later, particularly after World War I, rather than internal social reforms. Lastly, establishing a new economic system does not align with the Progressive objectives, as the movement primarily aimed to improve the existing capitalist system rather than overhaul it entirely.