By the time Mount St. Helens finished erupting, a crater had formed at its top. Forests had been destroyed for miles and rivers had been blocked by debris. Clouds had even blocked out the
sun in the entire state. It took years for the environment to recover
What is the main idea of the passage?
A. Forests and rivers are affected by volcanic eruptions,
B. The effects of volcanic eruptions last for a long time.
C. The eruption of Mount St. Helens caused a lot of damage.
D. Mount St Helens erupted for a very long time.
