The statement that best explains how continents move through plate tectonics is:
D. nuclear radiation in Earth's core; matter heats and moves upwards; then cool areas of the mantle move down.
This description aligns with the theory of mantle convection, which is a driving force behind plate tectonics. As material in the mantle is heated by nuclear processes in the Earth's core, it rises, and when it cools, it sinks, creating convection currents that help move tectonic plates on the surface.