The correct answer is A) and B). Hope this helps.
        
                    
             
        
        
        
Answer:
1 : to institute (something, such as a law) permanently by enactment or agreement. 2 obsolete : settle sense 7. 3a : to make firm or stable. b : to introduce and cause to grow and multiply establish grass on pasturelands.
 
        
             
        
        
        
the answer is C. decreased variation in tail feather color because no form of the trait is advantageous.