Which statement correctly describes the practice of pastoralism in mongolia?
a. pastoralism was a social system that was based on raising livestock to provide for the needs of the people.
b. pastoralism was a social system that was based on using organized religion to united different regions.
c. pastoralism was a government system that was based on raising taxes from the earnings of peasants.
d. pastoralism was a government system that was based on appointing relatives to rule territories.