Complete question is;
What features of ocean basins are chains of basaltic rock that stretch more than 1.5 times Earth's circumference around the world at spreading centers?
Answer:
Oceanic ridges
Explanation:
The answer is oceanic ridges because they occur along divergent plate boundaries, where new ocean floor is formed as a result of the tectonic plates of the earth spreading apart. This separation leads to rise of molten rocks to the seafloor thereby producing very huge basaltic volcanic eruptions.
