Answer:
C
Explanation:
This layer is called the mantle and is formed of semi-plastic rocks (liquid enough to churn but the rocks are not really melted because of the enormous pressure of the overlying crust above). The layer is heated from below by the core that is hotter, The hotter mantle rises as it gets less dense while the cooler mantle at the upper layers sinks because it is denser. These convections drag with them the continental plates of the crust.
