Journalists and writers known as 'muckrakers,' such as Upton Sinclair and Ida Tarbell, played a key role in exposing social and political corruption during which historical era?

✓ Correct Answer: Option C

Muckrakers were investigative journalists during the Progressive Era (early 20th century) who exposed societal problems like corporate corruption, industrial abuses, and political machines, prompting widespread public demand for reforms.