Answer:
When the collision of two continental plates occurs
Explanation:
Mountain formation can result when the collision of two continental plates occurs. When two tectonic plates collide their edges crumple together thus pushing huge slabs of rocks to the earth surface which are known mountains. Mountains can also be formed by the actions of volcanoes which results when during the collision of two tectonic plates one of the plates is disposed inward thus exposing the mantle which will result in the spill of molten magma which later cools down to form the mountain.
Erosive activities of water can also form mountains.
