What Evidence Is NOT Used by Scientists to Decide Whether

Multiple Choice

What evidence is NOT used by scientists to decide whether a stratovolcano may be getting ready to erupt?

A) whether there are changes in the temperatures of volcanoes and erupted steam
B) whether numerous microearthquakes are occurring
C) whether a large bulge is growing on the flank of the volcano
D) whether there is an increase in sulfur oxide gas emissions from the volcano
E) whether red-hot molten magma is visible when looking down the crater