Reform movement that sought to return control of the government to the people. what is this reform group?

The reform group was Progressivism.

Explanation:

Progressivism was a broad movement centered on reforms that reached its height in the United States in the early 20th century.  It was created in response to the profound changes that were being experienced due to the rapid growth of .large corporations, and the levels of pollution and vulnerability of the general public to the negative dimensions of modernization. They were also outspoken about their fears of corruption in American politics. An example of a Progressive was Louis Brandeis who was an associate justice on the Supreme Court.

the 2nd option is the answer