D) about a quarter of Southerners had enslaved workers.
Not everyone in the South operated with slaves as their labor force. There were also smaller family farms and such. But those who did hold slaves in operating plantations held large numbers of slaves, and so the institution of slavery was a gigantic part of the Southern economy.
You can clearly tell that this is trying to persuade you into buying a product. this may work if they like the person selling the product. because it says "you buy one, lest I perish."