Answer:
D. They feared Lincoln would end slavery
Step-by-step explanation:
Slavery was very important in the South because of it's impact on the economy. Slaves provided labor without pay, making it much cheaper to produce goods. The South also focused on agriculture, and slaves would farm the land for Southerners. Without slaves, the production of goods in the South would decrease, which would negatively impact the economy. So, Confederates wanted to secede from the U.S. so that they could keep their slaves.