How Does Failure of an Artificial Levee Differ from Failure

How does failure of an artificial levee differ from failure of a natural levee?

A) The water spills slowly over the levee into its floodplain, dropping coarser particles next to the main channel.
B) The water flows faster, and the areas next to the levee are commonly buried under sand and gravel.
C) The water flows slowly, depositing valuable topsoil in the floodplain.
D) The water flows at the same speed as the river, limiting erosion.
E) There is no difference between failure of an artificial and a natural levee.