It would be the last option- when you want tot compare and contrast ideas
        
             
        
        
        
Answer: 
B - teach readers how to do something
 
        
                    
             
        
        
        
Its C the other answers dont fit the context
        
                    
             
        
        
        
Answer:
This may be a possible answer, But I could mess up.
Elders know more and have been here more. They were taught by their parents and their parents by their parents.  Young people are still learning and need help. Hope this helps!
[ This was a stolen answer, I'm only here to help.]