A) secretion of acids and ammonia
 
        
             
        
        
        
Because it is a learned behavior
        
             
        
        
        
I think it would be A. Helicase 
 
        
        
        
D) It is based on the position of rock layers. 
        
                    
             
        
        
        
Answer:
If you go to a local store, and get scar cream, like stretch mark cream, that would help a lot.
Explanation:
Hope this helped! :)
Please don't hurt yourself :(