During the 13th century, the Mongols conquered the Kievan Rus' and ruled for another two centuries. Which of the following was one result of the Mongol conquest of the Kievan Rus'?
A.
The Kievan Rus' lost much of their cultural identity.
B.
The Kievan Rus' became more isolated from European civilization.
C.
The Kievan Rus' were able to unite all Slavic people politically.
D.
Most of the Kievan Rus' converted from Christianity to Islam.