Rise Of Progressivism

Instructions:

Carefully read the following question, and submit your answer based on your readings and understanding of the subject.  Your answer should be at least a paragraph in length. Please proofread your submission–points will be deducted for sloppy work.

Name at least four factors contributing to the rise of Progressivism at the turn of the twentieth century.  Which do you consider to be the most influential?  Why?