What Happens to Wave Energy and Erosion When Riprap or Seawalls

What happens to wave energy and erosion when riprap or seawalls are installed?

A) Waves striking the riprap are reflected back against the incoming waves to lessen their overall effect.
B) Wave height rises against the wall, and more erosion occurs at the base of the wall.
C) Seawalls do not influence wave energy or erosion; they only create separation between the sea and structures.
D) Waves lose their energy against riprap or seawalls, so erosion is prevented in that area.
E) Waves pulverize the riprap and seawalls, creating sand that helps maintain the beach.