Question

lincoln steffens, ida tarbell, and upton sinclair were muckrakers.
what did they do?

they wrote the first gossip columns for urban newspapers.

they uncovered and reported on political and business corruption.

they met with political leaders to advise them about corruption behind the scenes.

they devised a systematic trash collection system for the city of chicago.

Explanation:

Muckrakers were Progressive Era journalists who exposed societal issues. Lincoln Steffens uncovered political corruption in cities, Ida Tarbell reported on monopolistic practices in the oil industry, and Upton Sinclair revealed unsanitary conditions in the meatpacking industry, all focusing on political and business wrongdoing.

Answer:

They uncovered and reported on political and business corruption.