The most controversial aspect of the compromise of 1850 was the

The opposition brought by the compromise between northern liberal states and southern slave states.  

Explanation:

Slave states proposed to expand slavery to the new lands that the United States acquired after the war with Mexico, however liberal states opposed to this. The most interested state to expand slavery to the regions was Texas.

the right answer is the end of world war ii

after the end of a global wwii all the nations involved, in an attempt to create an organization to maintain world peace. this agreement would work settling international disputes via negotiation and arbitration instead of leading the issues escalate to another war.

utah hope this