it does not constitute a minor relief feature in the ocean. It refers to trenches, which deep sea depressions with narrow basins, which are associated with strong earthquake and volcanic activity.

A is incorrect. Sea-mount is a minor relief feature. It refers to a mountain with a summit, which does not rise all the way to the surface of the ocean.

B is incorrect. Atolls are tropical islands formed by coral reefs.

D is incorrect. Guyot is a seamount with a flat top.