The answer is C. Either B or b
Convection currents direct the movement of Earth's rigid tectonic plates in the planet's fluid molten mantle.
In places where convection currents rise up towards the crust's surface, tectonic plates move away from each other in a process known as seafloor spreading.
So, I would say the answer is:
As convection currents drift across the oceans,
they bring the pieces of Earth's crust with them as the supercontinent breaks apart.
Glad I could help, hv a good day :)