Final answer:
The roots of the radical progressive movement can be traced to the Labor movement and the ideas of Eugene Debs.
Step-by-step explanation:
The roots of the radical progressive movement can be traced to the Labor movement and the ideas of Eugene Debs. The Labor movement, which advocated for the rights and better conditions of workers, provided a foundation for the radical progressives. Eugene Debs, a prominent labor leader and socialist, played a key role in promoting radical ideas and pushing for revolutionary change.