Answer: it represented the final chance for a lasting reconciliation between Union and Confederate forces on Southern soil
Explanation:
Fort Sumter guarded the harbor at Charleston, South Carolina, and was commanded by the Unionist Major Robert Anderson. Secessionists forces demanded total withdrawal of federal forces from the fort. Lincoln understood that giving up on Fort Sumter would be giving up the Union. He ordered the resupply of the Fort, but President Jefferson Davis and his Confederates decided to not follow Lincoln's decision. At four-thirty on the morning of April 12, the Confederate shelling of Fort Sumter began. And after 36 hours of crossfire, the Unionists lowered the flag on April 13. The fall of Fort Sumter started the Civil War and ignited a wave of bravado across the Confederate states. The guns of Charleston signaled the end of the waiting game.
Aside from connecting the East U.S. to the West U.S., the transcontinental railroad was also instrumental in driving a gap through the confederate territories and ending the reconstruction era. (Choices A and D are the answers.)
Your correct answer would be nativism as that is the political policy that people native to a country are more important than those who are moving here from another country. let me know if you have any further questions :)