Answer:
They are in different states and have different temperatures.
Step-by-step explanation:
Plate tectonics is defined as the breaking of the Earth's strong outer layer into a mosaic of plates that move into a mechanically weaker layer.
The two types of layers responsible for Plate tectonics or tectonic activity are crust and mantle. These two are most responsible for tectonic activity because they are in different states and have different temperatures. Due to this, pressure in the crust (below the mantle) forces mantle magmas that erupt out of volcanoes, cool, and solidify through cracks to Earth's surface.