Question

by which mechanism does older oceanic rock move at a ridge? magnetic forces move the rock. continents drift and move the rock. the ridge subducts and moves the rock. new molten material rises and moves the rock.

Explanation:

At mid - ocean ridges, new molten material (magma) rises from the mantle. As this new material cools and solidifies, it pushes the older oceanic rock away from the ridge. Magnetic forces are not the main mechanism for moving oceanic rock at ridges. Continental drift is a broader concept related to the movement of continents over long periods and not the direct mechanism at ridges. Subduction occurs at trenches, not ridges.

Answer:

New molten material rises and moves the rock.