D. They acted to support big business.
During the Progressive Era (1890-1920), ending with the administration of President Woodrow Wilson, actions had been taken to regulate businesses and address the problems caused by industrialization and urbanization. But promising what was dubbed a "return to normalcy," the Republican party took control of both houses of Congress and the presidency in the 1920 elections. The Republican presidents of the 1920s (Harding, Coolidge, and Hoover) went in the opposite direction of previous Progressive Era policies. The were inclined to let corporations operate in a more unregulated fashion. They also raised tariffs to protect American business, and cut taxes for wealthy business owners.