Q: You are presented with the quiz "How are limestone caves formed?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "stalactites are formed by deposition" and "limestone caves displaying stalactites". So, what's the best answer to the question?

[I] less water
[II] Depositions
[III] They're manmade
[IV] erosion
[V] Water expanding
[VI] Thunderstorms
[VII] They're made by animals
[VIII] rainfall
A:
[II]