Answer:
The correct answer is a caldera.
Step-by-step explanation:
A caldera is one of the most catastrophic volcanoes that exist.
The way they are formed is unique, since it has the shape of an inverse volcano.
They come to be seen as a great depression because a very large magma chamber is accumulated under the ground because of the gases they contain inside, which generate very high pressures.
Cracks are formed to give way to the escape for these gases which are formed from the magma chamber to the surface.
When this pressure can be released the chamber sinks and finally reveals the final shape of the caldera.