The best response that explains why the New South’s primary goal was moving from an agricultural to an industrial economy is:
After the Civil War and Reconstruction, the South could not rely on free labor to make a profit.
This captures the reality that the post-Civil War South needed to find new economic structures and practices since the previous reliance on slave labor was no longer viable. The shift towards industrialization was a way to adapt to these changes and seek new sources of economic growth.