According to the reports given by Ethan Andrews, a source informed him that slave labor on Virginia tobacco plantations was no longer profitable and that slavery in Virginia was sustained primarily by A. developing new commodities for export. B. federal tax subsidies. C. selling slaves into the cotton planting south. D. state tax subsidies.

C. selling slaves into the cotton planting south.

Explanation:

Between the early and mid 19th century Virginia saw its tobacco plantations losing profitability as the crop dwindled. The slave owners there could therefore no longer afford to keep large numbers of slaves as they had to feed them. Some decided to free them but most decided to sell them further South.

In what has been termed the Slavery Trail of Tears, over a million slaves were moved from Virginia to the South in the years between the beginning of the century and the American Civil War. This domestic slave trade sustained slavery in Virginia and gave a lot of white men employment opportunities.