I would say that D is the most important reason ie to monitor the location and magnitude of seismic activity to attempt to find patterns which may lead to the ability to predict the next earthquake in the world though individual seismic stations probably monitor more the seismic activity in their own country mostly though perhaps not exclusively.
        
                    
             
        
        
        
Storms are caused by the collision of air masses that have different temperatures and humidities.
        
             
        
        
        
Answer:
i could maybe answer this if you could give me a picture :)
Explanation:
 
        
                    
             
        
        
        
The U.S economy produce 20% of the world's output