Volcanoes are often formed at plate boundaries. this is a convergent plate boundary. from the choices listed, pick the correct description of what happens before the volcano forms.

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101