I think (a) because the ocean floor is the crust which is mainly were shallow earthquakes occur. I'm not sure if this is right or not sorry :)
Answer:
false Metamorphic rocks can only form from pre-existing rocks. Metamorphic rocks only form as a result of metamorphism of igneous or sedimentary rocks. Rock melting to form magma defines the upper limit of metamorphic processes. The oldest rock exposed to Earth's surface is a metamorphic rock.
Explanation:
hope this helps sorry if it doesn't have a good rest of your day :) ❤
