If an Ash Flow Approaches You from Across a Kilometer-Wide

Multiple Choice

If an ash flow approaches you from across a kilometer-wide lake,are you likely to be safe or not? Explain why.

A) Safe. Hot ash flows would chill and stop as soon as they hit cold water.
B) Safe. Ash flows move along the ground; they would continue harmlessly underwater.
C) Safe. Hot ash flows would boil the water, and that would stop them.
D) Not safe. A fast-moving ash flow would cause a deadly tsunami wave.
E) Not safe. Ash flows can cross much wider bodies of water.