How Did the Italian States Manage Relationships Among Themselves After

How did the Italian states manage relationships among themselves after multiple wars in the fifteenth century?

A) They devised a diplomatic system with assigned resident ambassadors to one another's capitals.
B) They selected champions from each city to serve in tournaments; the winning champion meant that city dictated terms.
C) The papacy was chosen as the final arbiter for crucial disputes.
D) A special court was created with delegates from each city to hear disputes.
E) The Holy Roman emperor was called upon to settle major disputes.