Answer:
I would say B - Convection
Step-by-step explanation:
it is volcanos and earthquakes that move the tectonic plates... but those act like convection currents...
-Solar Winds come from the Sun and they are reflected off of Earth's magnetic shield so that can't be correct.
-Gravitation does play a role yes but I can not say that it actually causes it... (Gravity holds everything in orbit and also together... and it helps keep things on Earths surface -it is the reason why we can still breath-)
-Unknown - Still Investigating, The reason why the tectonic plates move "was" discovered... or at least it is believed to have been. But I do not doubt that they are still studying it... because they probably are still investigating
-The convection currents move the plates. Where convection currents diverge near the Earth's crust, plates move apart. Where convection currents converge, plates move towards each other.
I have a nice day and I hope it helps!
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