Answer:
d.) Feudalism
Step-by-step explanation:
Feudalism refers to the economic, social and legal in western Europe during the early Middle Ages in which there would be an agreement that a person would hold and farm land from a lord in exchange for receiving protection or simply military service.
Feudalism was therefore a political and social organization in which the lord performs a distinct military service in exchange for a land farming service performed by someone else.
Therefore, the political and social organization of Western Europe in which each distinct class performs mutual and reciprocal obligations for the overall integrity and cohesion of the FIEF may best be described as d.) Feudalism.