Which of the Following Is a Way That Pastoralist Nomads

Which of the following is a way that pastoralist nomads helped contribute to the rise of new territorial states in Afro-Eurasia around 2000 BCE?

A) Nomads introduced military technologies such as faster horse-drawn chariots.
B) Nomads introduced new ways to recruit and train bureaucracies.
C) Nomads introduced writing,which was essential to record keeping in larger,territorial states.
D) Nomads introduced new siege technologies for attacking walled cities.