Question

According to the theory plate tectonics, the Earth's crust is broken into about 12 plates that float on hotter, softer rocks in the underlying mantle. These plates move about the Earth, just inches each year. These slight movements are responsible, in great part, for the earthquakes and volcanoes that happen on Earth. What is the source of energy that drives this plate movement?
Responses
A the subducton of the sea floorthe subducton of the sea floor
B convection currents in the mantleconvection currents in the mantle
C the different densities of the oceanic and crustal platesthe different densities of the oceanic and crustal plates
D the friction force between the plates that move past each other

Answer 1

B — convection currents in the mantle.

Mantle convection (heat-driven circulation of hot, less dense rock rising and cooler, denser rock sinking) provides the main driving forces (plus related effects like ridge push and slab pull) that move the plates.