Final answer:
Option (D), Southern slave owners ignored the Emancipation Proclamation and continued supporting the Confederate cause in the Civil War.
Step-by-step explanation:
The reaction of Southern slave owners to the Emancipation Proclamation was one of defiance and outright rejection. The Emancipation Proclamation, issued by President Abraham Lincoln on January 1, 1863, declared all slaves in Confederate states to be free. However, Southern slave owners, who did not recognize federal authority, largely ignored the decree and continued to support the Confederacy in the Civil War.
The proclamation also redefined the war to include the aim of overthrowing slavery by force of arms, which resulted in the eventual enlistment of freed slaves into the Union army, further bolstering the Union's position.
Although the Emancipation Proclamation was limited, only targeting rebelling states, and did not immediately free all enslaved people, it signified a crucial shift in the Union's war goals and laid the groundwork for a future without slavery.