Question

multiple-choice question
what happened on march 31, 1980?
the major eruption that destroyed the mountain
the two craters merged as explosive eruptions continued.
a larger earthquake

Explanation:

To answer this, we recall events related to Mount St. Helens (since the options relate to eruptions/craters/earthquakes). On March 31, 1980, the two craters on Mount St. Helens merged as explosive eruptions continued. The major eruption that destroyed the mountain was on May 18, 1980, and the "larger earthquake" context here doesn't match March 31, 1980's key event.

Answer:

The two craters merged as explosive eruptions continued.