Mid-Ocean Ridges (MORs),which Are the Sites of New Oceanic Crust

Multiple Choice

Mid-ocean ridges (MORs) ,which are the sites of new oceanic crust formation,are linear mountain chains that run along divergent plate boundaries.Why does an MOR sit up higher than the surrounding oceanic crust?

A) Hot materials are less dense and shrink,thus the new crust will sit higher than the surrounding crust.
B) As the hot magma exits the MOR,it shoots up higher than the surrounding crust.
C) Hot materials are less dense and expand,thus the new crust will sit higher than the surrounding crust.
D) Hot,geothermal waters cause the new crust to expand and sit higher than the surrounding crust.