The correct answer to this question would be alternatives:
A)"expansion into new territories."
D)"the debates issue of slavery."
E)"the tug-or-war over parts of the states several southern states."
The American Civil War was an important mark in American History, and the three elements cited above are really related to the War.
Slavery was really an issue, as wells as states expanding their territories and influence. The tension because of ideological differences was off the charts.