Final answer:
Option C. The newest source of revenue in the South is the space industry, as traditional industries like tobacco and cotton are long-established and mining does not present a new revenue stream either.
Step-by-step explanation:
A fairly new source of revenue in the South is C. the space industry. Considering traditional Southern industries such as tobacco farms, cotton mills, and mining, have been established revenue streams for many years. Tobacco, once the most lucrative product of the Chesapeake colonies, and cotton, a dominant crop in the South's economy before and after the Civil War, are not new sources of revenue. The space industry has emerged more recently as a significant economic growth area, particularly with the rise of commercial spaceflight and related technologies.