Final answer:
Business leaders, politicians, and tenement owners likely resented muckrakers for exposing social and political issues, as this threatened their positions and the status quo.
Step-by-step explanation:
Business leaders, politicians, and tenement owners likely resented the exposure of social and political issues by muckrakers. As investigative journalists, muckrakers shone a light on problems such as corrupt politics, poor working conditions, and substandard living conditions of the working class. They provoked public outrage and inspired change, often leading to the development of legislation aimed at reforming the exposed injustices. Therefore, rather than being admired, supported, or ignored, the efforts of muckrakers were seen as a threat to those in positions of power who benefitted from the status quo. The intense investigative focus on the negative aspects of society, much like the figure in The Pilgrim's Progress who was obsessed with raking mire, is what led President Roosevelt to coin the term "muckrakers" in a somewhat pejorative sense.