Answer:
A.  human-environment interaction
Explanation:
This kind of study which involves impact of human activities on the environment falls under the human-environment interaction theme of geography. 
It entails how human activities continues to shape his immediate environment. 
- Geographic theme of location is associated with where on earth something can be found. It could be absolute or relative location. 
 - Geographic theme of place involves the physical and human setting of a place. 
 - Geographic theme of region defines a particular area which are classified under some certain categories. 
 
The fitting answer to this problem is the theme of human - environment interaction. 
 
        
             
        
        
        
The capitol of Los Angeles is California.
        
                    
             
        
        
        
The state of the object on which the net force is zero is 'constant uniform motion',
or 'unaccelerated motion'.