Hi there! The answer is C. feudal system.
The feudal system - also known as feudalism - is the name that defines the political, social and economical system in Western Europe after the decline of the Roman Empire. The system globally existed during the early and central Middle Ages.
In the feudalism we can distinguish four different social layers, in which the members all had a different function in society. The four layers are: kings, nobles (or lords), knights and peasants.
~ Hope this helps you!
