Explanation:

Volcanoes are known as the safety valves of nature because they periodically release the pressure that builds up because of tectonic activity in the Earth's crust and even lower layers. When pressure builds up, eruptions occur. Magma shoots up through the volcano and flows down its sides.A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. Earth's volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle.