Early settlers along the Huang He tried repeatedly to control the river's flooding by building levees, but these failed to hold back the water. During the Xia Dynasty a method was finally discovered that worked. What was that method?

A.
building canals to direct floodwater out to sea

B.
damming the river near its source

C.
constructing levees out of stone rather than dirt

D.
digging out the river to make it deeper