Answer:
a) the study of the political, social, cultural, and economic setting surrounding a historical event 
Explanation:
 
        
             
        
        
        
Tony Stark and Captain America     jk sorry. 
The Union and Confederates 
 
        
                    
             
        
        
        
I’m pretty sure it was the imbalance of power. Then there was the war, and Political corruption was a big one too
        
             
        
        
        
In 1600s the planter class increasingly relied on African slaves for labor majorly because slaves were offering cheap labor now that the planters didn't have to pay for this form of labor. This led to most of them foregoing traditional indentured servants who would be paid for  their labor and instead opted for African slaves.