This refers to the geological processes, mostly large-scale movements of Earth's crust, that result in the formation of mountains first two letters are mo
btw

Mountaing building.

Explanation:

Mountain building is a process by which, through the movement of tectonic plates over time, undulations and elevations are generated on the face of the earth, which end up originating the mountains that we see today.

Thus, the great mountain ranges and notorious elevations of planet Earth have originated through the collision of different tectonic plates, just as the Andes Mountains originated from the collision of the Pacific Plate and the South American Plate.