What happens to old oceanic crust as new molten material rises from the mantle?

 The correct answer is :  The new material is responsible for separating the old material and stacking it out from the crest.

Explanation:  At mid ocean ridge, molten material leaves the mantle and erupts. The old crust extends closer to the continents. The process by which the ocean floor sinks into the mantle is called subduction.

aliens arent real sorry bud