Read the excerpt and answer the question below. "If we do not exclude slavery from the territories, it will exclude us... Where slave labor strikes
its roots deep into the soil of a territory, free labor will not grow, but perish. We are all
personally interested in this question, not indirectly and remotely, as in a mere political
abstraction, but directly, pecuniarily and selfishly."
-Source: Speech given by Oliver P. Morton, 1860
Which of the following was a major difference in economic development between the North and the
South in the 1850s?