Final answer:
Muckrakers were journalists who significantly contributed to the rise of the Progressive Era by exposing corruption in business and government, which galvanized the public and spurred on Progressive activists to advocate for reforms.
Step-by-step explanation:
Muckrakers significantly contributed to the rise of Progressivism in the early years of the 20th century predominantly by exposing widespread corruption in business and government. They aimed to unveil the problems plaguing the nation, such as child labor, anti-trust issues, big business influences, and unsafe working conditions.
These investigative journalists published their findings in books and magazines, which then influenced public opinion and spurred Progressive activists to push for legislation aimed at reforming the ills of industrial America.
Their work drew attention to the social injustices and economic disparities of the Gilded Age and the inadequacy of the federal government’s laissez-faire approach since Reconstruction. This attention energized the Progressive movement, which sought to correct these inequities through government regulation.
By publicizing societal issues, muckrakers galvanized middle-class Americans, who started joining reform organizations in greater numbers, leading to an era marked by social and political change aimed at improving the overall state of American society.