which phrase describes a lava plateau?\nsteep - sided mountain\ngently sloping mountain\n hardened magma in…

Brief Explanations:

A lava plateau is formed by repeated lava - flows that spread out over a large area. It has a gently sloping surface. A steep - sided mountain is more characteristic of a stratovolcano. Hardened magma in a pipe is related to a volcanic neck. Volcanic material in valleys is not the description of a lava plateau.

Answer:

gently sloping mountain