The correct answer is: D. Fold mountains.
Fold mountains are formed when two tectonic plates collide and one plate is forced under the other. The rocks on the top plate are folded and faulted, and the mountains are created. The Himalayan mountain system is an example of a fold mountain.
Volcanic mountains are formed when magma erupts from a volcano and cools to form lava. The lava builds up over time, and the volcano grows taller. The Hawaiian Islands are an example of a volcanic mountain range.
Residual mountains are formed when the land around them is eroded away, leaving the mountains standing. The Appalachian Mountains are an example of a residual mountain range.
Block mountains are formed when the Earth’s crust is uplifted or downdropped, creating blocks of land that are different heights. The Sierra Nevada Mountains are an example of a block mountain range.