Which statement explains how mantle plumes produce hotspot volcanoes? a
Mantle plumes push through weak zones of the crust, emerging at Earth’s surface in a plume-shape in areas that are not necessarily the boundaries of tectonic plates.
b
Mantle plumes consist of a molten mix of rock that is much hotter and less dense than surrounding rock and so rises through the mantle.
c
Mantle plumes are formed when tectonic plates move over hotspots in the mantle.
d
Mantle plumes originate near the mantle core boundary, where there is a sharp thermal gradient.