On the pH scale, simply put, 1 is the most acidic, 14 the most basic, and 7 is neutral. So if it is basic, it would have to be above 7, and 8 is the only one above seven, so your answer is D.
Hot magma rises from the mantle at mid-ocean ridges pushing the plates apart. Earthquakes occur along the fractures that appear as the plates move apart.: