Answer:
B. toward the center of the earth
Seafloor spreading<span> is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. </span>Seafloor spreading<span> helps explain continental drift in the theory of plate tectonics. </span>
Until the early Proterozic there were only negligible amounts of free oxygen in the atmosphere
The answer is A extreme proverty
