Calderas Are Formed When ____

Multiple Choice

Calderas are formed when ____.

A) low-viscosity magma flows out into very large areas and cools
B) pyroclastic flows mix with lava flows
C) the volcanic pipe is plugged and the increase in pressure causes a huge explosion
D) part of a magma chamber drains and the mountain's summit collapses into the vacated space below
E) large explosions at the base of a volcano cause the volcano to collapse