Answer:
A) Northern and Southerners disagreed over the spread of slavery.
Explanation:
"What led to the outbreak of the bloodiest conflict in the history of North America? A common explanation is that the Civil War was fought over the moral issue of slavery. In fact, it was the economics of slavery and political control of that system that was central to the conflict. A key issue was states' rights."
Soldiers also made dugouts and funk holes in the side of the trenches to give them some protection from the weather and enemy fire. The front-line trenches were also protected by barbed-wire entanglements and machine-gun posts. Short trenches called saps were dug from the front-trench into No-Man's Land.
The dissolution of the union began in the 1980s
Answer:
The answer to this question is B