Based on the issues and tensions that followed the United States in the 19th century, and led to Civil War, the following are the options to fill in the blanks:
From the beginning of the U.S. as a nation, the issue of slavery had being a bone of contention between the North where there was no slavery, and the South which still practiced it.
It didn't help that new states were being added which would tip the balance in favor of either the Free or Slave states.
Things came to a head when the Republican Party nominated Abraham Lincoln to be its presidential candidate. This angered the South as both the Republicans and Lincoln were abolitionists.
When Lincoln was elected, the South decided to secede with South Carolina being the first to do so.
Find out more on the American Civil War at https://brainly.com/question/1020924
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