I believe it is C. This is because in communism, citizen's power is limited rather than in socialism.
The most important reason was economical: slavery was profitable for slave owners in the South, and they were against its abolishing. The southern plantations were very work -intensive, so a lot of work was needed and slave labour was a very cheap source of labour that the owners didn't want to give up upon.
the correct answer is <span>B. The Southern plantation economy depended on slavery. </span>
The American soldiers were rested and brought energy to the Allies. The spirit of the Allied soldiers improved significantly. Unites States industries produced much-needed supplies for the Allies. Military equipment and food were provided to assist the Allies in their fight against the Central Powers.