What does the presence of new rock near an oceanic ridge indicate? A: There is always a deep-sea trench underneath
B: There is evidence of seafloor spreading
C: They are made from oceanic crust
D: They have iron oriented in different directions

This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.