Option A, hot spot, is the right answer.
Mantle plumes are regions of warm, up-welling covering. A hot spot occurs over the plume. It generates the magma that emanates by the unbreakable plates of the lithosphere and provides active volcanoes at the surface of the earth. In other words, the hot spots are found in the mantle where cliffs melt to form magma. It creates a volcanic region a few hundred kilometers across.
