Final answer:
The first southern state to secede from the Union was South Carolina on December 20, 1860. This marked the beginning of a series of secessions that led to the Civil War.
Step-by-step explanation:
The answer to your question, "Which of the following southern states was the first to secede from the Union?" is D) South Carolina. The secession of southern states from the Union was a crucial event in the history of the United States, leading to the Civil War.
On December 20, 1860, South Carolina became the first state to secede. Thereafter, other Deep South states, including Mississippi, Florida, and Alabama, followed in rapid succession.
Interestingly, not all states that contained slaveholders joined the Confederacy, as your options might suggest. For instance, four crucial slave states (Delaware, Maryland, Missouri, Kentucky) remained within the Union despite internal divisions.
Learn more about Secession of Southern States