The answer is:
B. they rebelled against the harsh rule of the shang
hope this helps, Pal
A. Urban II
These incursions prompted the emperor of Byzantium, Alexius I Comnenus to send a delegation to Piacenza, Italy, asking Pope Urban II in March 1095 for help against the Turks. On November 27, 1095, in Clermont, France, Pope Urban II called for a crusade to help the Byzantines and to free the city of Jerusalem.
Shows a relationship that does not always indicate cause and effect ,
Because they had a different currency than the rest of the world and wanted to compete in what historians call the "The Great Coin Race" which started in 19 A.D. and ended in 1339. The soon regretted this.