Final answer:
The best evidence supporting the hardship of serfs in Middle Ages Europe is their unfree status, obligatory labor for their lord, and the fact that they had little income and few rights, severely limiting their life options.
Step-by-step explanation:
The evidence that best supports the reasoning that serfs were the most abused group in Middle Ages Europe and their work held together the entire system of Feudalism while they were overworked and economically and socially taken advantage of comes from the description of their obligations and living conditions under the feudal system. Serfs were unfree laborers who were not enslaved but tied to the land. They had to provide labor and goods to their lord, pay rent in the form of labor, and live under harsh conditions with little income to spare, often at subsistence level. Specifically, the evidence indicating they could not leave the land, marry, or undertake other work without the lord’s permission, as well as the fact that serfs paid rents through labor which kept them in servitude, strongly supports the claim of their hardship.