Why is Mt. St. Helens known as an active volcano? A) The Cascade Mountain Range in Washington is part of the Ring of Fire that contains over 160 active volcanoes.

B) Throughout history, Mt. St. Helens has been known to erupt regularly, causing the death of 56 people every year.

C) Volcanoes are active if they have erupted in the last 10,000 years, and Mt. St Helens erupted only a few decades ago, in 1980.

D) When Mt. St. Helens erupted in 1980, 56 people were killed and the surrounding landscape was changed forever.