Verified Answer :

a vent in the earth's crust through which lava, steam, ashes,
etc., are expelled, either continuously or at irregular intervals.

Or


a mountain or hill, usually having a cup-like crater at the
summit, formed around such a vent from the ash and lava expelled through
it.

Answer:

a volcano is an opening in the crust of the earth through which molten rock material or magma comes out.

Explanation: