Who were the muckrake A. Civil war veterans
B. City sanitation workers
c. Conservative politicians
O D. Journalists and reformers

D. Journalists and reformers

Explanation:

They were the journalists in the Progressive Era (1890's to the 1920's). Upton Sinclair and Ida Tarbell were two of them.

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roosevelt believed that in light of the country's recent military successes, it was unnecessary to use force to achieve foreign policy goals, so long as the military could threaten force. this belief, and his strategy of “speaking softly and carrying a big stick,” shaped much of roosevelt's foreign policy.