What was the PRIMARY reason for the collapse of the Kievan Rus

Of the following choices, which ones are characteristics of west african society? select all that apply. a. arabic was the main language used when trading with other societies. b. christianity was the only religion practiced in villages. c. slaves had no rights and were only given specific farming tasks. d. skilled workers were a higher level in the caste system than traders. e. religious rituals encouraged the honoring of ancestors.