The supreme law of the land is B) The U.S. Constitution.  
I hoped this helped! Please rate, thank, and pick the Brainliest answer (not necessarily mine!). Thanks, it really helps! :)
        
                    
             
        
        
        
Main advantages would have been that there are bigger cities, better doctors and bigger businesses. Also if you were black, slavery wasn't allowed. Disadvantages would've been mostly political, like the fact that the economy could crash at any time. and that second part is your opinion fam
        
             
        
        
        
Does this question have multiple choice answers? I'd love to help if you still need it.