Answer:
I'd say that it was the assassination.
Step-by-step Explanation: I had a test similar to this, and it was the assassination.
Answer: Without big farms to run, the people in the North did not rely on slave labor very much. In the South, the economy was based on agriculture. The North wanted the new states to be “free states.” Most northerners thought that slavery was wrong and many northern states had outlawed slavery.
Explanation:
The U.S. entered World War I because Germany embarked on a deadly gamble. Germany sank many American merchant ships around the British Isles which prompted the American entry into the war. World War one had huge effects on America including highly productive industry that preceded the Great Depression, jobs given to woman, which helped pass the nineteenth amendment, and a new kind of diplomacy and antiwar sentiment that affected America's entrance into World War II.