B! The strongest characteristics will survive when the weak ones won't
        
                    
             
        
        
        
A Respiration by animals CO2 is being added.
B trees burning same
C tree leaves removed
D oil added
        
             
        
        
        
Macromolecules, hope this helps.
        
             
        
        
        
Explanation:
Owl has the role of the tertiary (third) consumer, in above food web. 
 
        
                    
             
        
        
        
The offspring is unique and is not like its parent plant.