Answer: Option (A) is the correct answer.
Step-by-step explanation:
Heat from inside the surface is transferred to its surface through conduction. As in conduction, there is transfer of heat from hotter substance to colder substance when placed together.
Therefore, less dense material rises towards the surface by the process of convection and more denser (colder) material remains inside the Earth.
Thus, we can conclude that warmer material is pushed to the crust.