The Yellow River (Huang He River) does not contain as many cities along its banks as other rivers in China. Why is this the case?

Responses
A It is found entirely in a desert.It is found entirely in a desert.
B It is plagued by rapid currents and constant flooding.It is plagued by rapid currents and constant flooding.
C It was re-routed by the Communist government in 1950.It was re-routed by the Communist government in 1950.
D It was controlled by bandits and warlords until 1949.

D It was controlled by bandits and warlords until 1949.