What factor contributed to Genghis Khan’s expansion of the Mongol empire?
A.
He expanded trade routes by building a complex system of canals and waterways.
B.
He led a ruthless military into foreign land, using powerful weapons to break down city walls.
C.
He established a new social order that led to the creation of a stable government.
D.
Inventions and innovations during his time of leadership helped industries to grow..