Why is the lithosphere able to move along with the earth’s crust?

The lithosphere is a hard shell of the earth, therefore, when it moves, the earth’s crust also moves. The forces that move the lithosphere and the earth’s crust are called the internal forces of the earth. They are formed during the decomposition of radioactive particles and the displacement of the melt of the outer cover. Internal forces, touching the lithospheric plates, move them to the side, generating movement along the faults.