Southern Secession is the event or issue that historians can gain.
        
             
        
        
        
Answer:D. Us jobs were lost as corporation took advantage of cheap overseas labor
Explanation:took the test 
 
        
                    
             
        
        
        
Secret diplomacy was a major factor based on the fact that led to fear between all the nations and confusion. Nationalism and imperialism is a factor, scramble for Africa, Archduke fradana has some ties based that his death lead to more retaliation in the Balkans which wanted to be independents do Austria-Hungary and Russia fought over for.