What event triggered the main eruption of Mount St. Helens in May 1980?
A. Magma encountered groundwater and exploded.
B. A landslide removed rocks and released pressure on the magma.
C. Melting snow caused a huge steam eruption.
D. All of these choices are correct.
Answer: B
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A) humidity. B) deposition. C) sublimation. D) water. E) transpiration.
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