Convergent
boundaries or destructive plate boundary due to subduction, is an actively deforming
area where two or more tectonic plates of the lithosphere move towards one
another and collide. As an effect of pressure, plate material and friction
melting in the mantle, volcanoes and earthquakes are common near convergent
boundaries. Subduction or continental collision is created when two plates move
towards one another, depending on the nature of the involved plates. During
these collisions (between two continental plates) Himalayas and large mountain
ranges are formed.
I can't Understand you Sorry
The main mechanism through which the layering happened is gravity: it pulled the heavier, denser material to the center, leaving the less dense material on the surface.
The material that was on the outside cooled quicker, but this was the result, not the cause.
The answer is
<span>2) Gravity caused more-dense material to move toward the center of each planet.</span>
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