8. The process that drives the movement of tectonic plates is called (a) volcanism, (b) subduction, (c) mantle convection, (d) ocean currents, or (e) hot spots? 9. Which of these rocks are produced under increasing pressure and temperature from a pre-existing rock: (a) sedimentary, (b) igneous, or (c) metamorphic rocks? 10. True (a) or false (b): a hot spot is a place where oceanic lithosphere disappears under continental crust 11. Which of these terms refers to the formation of new oceanic crust: (a) hot spots, (b) orogeny, (c) sea floor spreading, (d) subduction, or (e) downdraft? 12. The earth's mantle is composed of: (a) granite, (b) peridotite, (c) anorthosite, (d) graphite, or (e) obsidian