Fact 1: The movement of tectonic plates causes volcanic eruptions.

Fact 2: Among the most destructive types of debris flows are those that accompany volcanic eruptions.

Given the two facts above, answer the question "the movement of tectonic plates causes what?" with the following options: 
- friction
 - erosion
 - to move people
 - climate
 - debris flows
 - flooding
 - Movement
 - global warming


 

     debris flows    