Final answer:
The four early-twentieth-century muckrakers and their target exposés were David G. Phillips (the condition of blacks), Ida Tarbell (Standard Oil Company), Lincoln Steffens (city governments), and Ray Stannard Baker (United States Senate).
Step-by-step explanation:
The early-twentieth-century muckrakers and their target exposés are as follows:
- David G. Phillips: the condition of blacks
- Ida Tarbell: the Standard Oil Company
- Lincoln Steffens: city governments
- Ray Stannard Baker: the United States Senate