Options 1st and 5th follows.
A volcano is a crack in the crust of a terrestrial-mass element like the Earth, which releases burning pumice, gases and volcanic ash, to emerge from a magma body beneath the exterior. The volcanoes that have remained quiet for years but might perhaps explode again are known as the Dormant Volcanoes. The dormant volcanoes over a course of time remain active internally and thus erupt.