What role do you think volcanoes have played in the formation of earth's surface features as they exist today?

Volcanoes have played an important role in the formation of the Earth's surface features by providing it with hilly and mountainous terrains, surface undulations and depressions.

Explanation:

The eruptions and cooling of volcanoes provided the Earth with required undulations that are necessary for the formation of natural valleys and hills. The volcanic dust also helped the surface soil become more fertile and favorable for the growth of more and more plant species. Moreover, volcanoes also helped by bringing to the top the minerals existent in the lower inaccessible layers of the Earth's crust.

Cause of he different elevations  hope this ?