The Overall Unity of the Muslim World Disintegrated During the Tenth

The overall unity of the Muslim world disintegrated during the tenth and eleventh centuries because of:

A) a special tax levied on Jews and Christians.
B) failures among the Umayyad rulers of Spain.
C) repeated attacks by the Mughal empire of India.
D) economic problems and a stagnating intellectual life.
E) the fractured political unity of the Islamic world exacerbated dissent and tension within Islam itself.