Answer:
d) their nobility
Step-by-step explanation:
During feudalism, the nobility played a crucial role in protecting and maintaining the kingdoms of Europe. They were the land-owning aristocracy who held significant military and political power, and were expected to provide loyalty, service, and military assistance to their kings in exchange for land and other privileges. The peasants, on the other hand, were generally tied to the land and had limited rights or freedoms, and thus had little direct influence over the ruling of the kingdom. While traders and other members of royal families may have had some influence, it was ultimately the nobility who had the most power and responsibility in feudal societies.