A. By causing plates to move against each other
Tectonic plate boundaries are the regions where tectonic plates interact, and their movement can lead to the formation of various landforms. For example, when plates collide (convergent boundaries), they can create mountains or cause one plate to be forced beneath another (subduction), leading to volcanic activity. Conversely, when plates move apart (divergent boundaries), they can create rift valleys and mid-ocean ridges. Therefore, the movement of plates at these boundaries directly influences the shape and elevation of the Earth's surface.