Ridges in the Middle of the Ocean Are Places Where

Ridges in the middle of the ocean are places where

A) one plate slides under another, returning older crust to the mantle.
B) plates slip sideways relative to one another.
C) hot mantle material rises upward, creating volcanic islands.
D) plates push together, creating ocean mountain chains.
E) hot mantle material rises upward and spreads sideways, pushing the plates apart.