Answer:
I think it's knights. because most nobles or lords were accompanied by knights. so they can't be a vassal for a lord
 
        
                    
             
        
        
        
The correct answer to the question is Option no. D Northern states profiting and southern states struggling. 
In those times the Northern States were had higher incomes and living standards compared to the Souther States. 
Hence, this cartoon illustrastes the differences in the economic conditions within the North and the South.