Answer:
The feudal system was in essence a substitution for the laws and security that were lost when the Roman Empire declined (the answer is c. laws / security)
Step-by-step explanation:
The feudal system was not conceived as a political sytem per se, François-Louis Ganshof defines feudalism as: " feudalism describes a set of reciprocal legal and military obligations among the warrior nobility revolving around the three key concepts of lords, vassals and fiefs." but is not seen as a substitution of the order and government because of the nature of system, the main reason why the Roman Empire collapsed was due the inability of the Emperor to control and sustain far away provinces that were in constant attack by the barbarians, because of that the emperor hired a lord to administrate and protect the land with the help of vassals (mostly had military obligations and where supported by knights), thats why the answer is option C and not D.