I would say All Of The Above.
        
             
        
        
        
D all of the above, they all contribute to seasons
        
             
        
        
        
They came from <span>Scandinavia, Italy, Poland, and Russia. Hope that helps! :)</span>
        
                    
             
        
        
        
Answer:
 The longest time period is eons. 
 
        
                    
             
        
        
        
<span>These three should be the most pressing problems
-illegal immigration
</span><span>-lack of skilled labor
</span><span>-aging pollution</span>