Which portion of the continental margin serves as a boundary between the oceanic crust and the continental crust

Continental rise

Continental margin is composed by three parts, the continental shelf, continental slope and continental rise. The continental shelf is located near the continental crust just a few kilometers and the middle portion of the margin, continental slope and continental rise which is 2,000 - 3,000 deep near the ocean floor. In the lithosphere, between continental crust and oceanic crust the continental rise is the boundary between these two. The continental rise is said border to which extends to abyssal plain or the ocean floor.