The most accurate comparison of the demographics of those living in the lowcountry and backcountry of South Carolina is:
The lowcountry had a majority enslaved Black population with a White minority, while the backcountry had a majority White population.
This statement reflects the historical context where the lowcountry, particularly due to its plantation economy, had a significant enslaved Black population, while the backcountry was more rural and had a more varied population that was predominantly White.