Respuesta :
The correct answer is A) The secession of several Southern states.
After the election of 1860, many Southern states decide to leave (aka secede) the Union. It started with the state of South Carolina in December of 1860. Within a few months, seven other states like Mississippi, Georgia, Florida, etc. left the Union as well. When they all seceded they joined together to develop their own nation called the Confederacy. This secession, followed by the firing on Fort Sumter, would help lead to the beginning of fighting between the Union and Confederacy.