C: to stop cities from fighting during the Olympics.
The purpose of the Olympic truce was to establish a peaceful period of time around the time of the ancient Olympic Games in Greece, during which wars and hostilities between the participating city-states were suspended to ensure the safe passage of athletes, spectators, and official delegations traveling to and from the Olympic Games. The truce aimed to promote peace and reconciliation and allowed athletes and spectators from different city-states to come together and participate in the Olympic Games without fear of violence or conflict.