C. How did the formation of
the Iroquois League benefit
its member nations?

The Iroquois or Haudenosaunee are a historical indigenous confederacy in northeast North America. 

The Iroquois League was most significant because it helped to resist the expansion of Europeans in the area by helping the tribes. Each tribe also had its own leaders to make local decisions.

With the formation of the League, internal conflicts were minimized. The council of fifty ruled on disputes, seeking consensus in their decisions. 

Hope it helps.

the answer is d. party organizers, volunteers, voters and elected officials.