The genocide of the European Jews. so your second sentence is correct
        
                    
             
        
        
        
Answer: a.  The War Production Board helped factories quickly shift from only making consumer goods to making war materials.
Explanation:
A key part of the U.S. being able to join the Second World War and contribute so effectively in the time that it did, was the War Production Board's efficiency in shifting American consumer production to war materials for use by the U.S. military and the Allies. 
Thanks to the Board, companies shifted their focus from consumer goods even though there was initially some massive pushback. Following a national campaign, opposition subsided and the U.S. was able to pump out so much war material that the war would not have been won without. 
 
        
             
        
        
        
Answer:
The growth of the susurbs
 
        
             
        
        
        
Answer: matahari
Explanation: The ability to create all their own products allowed the colonies to become more financially independent from Great Britain