Answer: I believe the answer is pressure
Explanation:
Go to https://phs-year9.wikispaces.com/Group+4-+Tsunami%27s
The most appropriate answer would be magma. Lava is a magma that reaches the Earth's surface, which is technically it is also a magma, and magma is located below the Earth's surface.
Lava at Earth's surface or magma below Earth's surface cools and harden to form mineral crystals.
The subject of science is very broad. With that being said, I think there is no official regulatory board that decides the branches of science. Scientific developments are products of joined efforts of different scientists. These scientists could rebuke another's work provided there is evidence. As long as the theory is generally accepted by the scientists and no one rebukes it effectively, then it is a generally accepted fact and everyone adapts it.
Hence, the answer is B.
