That soldiers gave their most, that the soldiers fully devoted to their job.
Steam boats, rail roads and telegram made communication and work easy and faster.
I'd go with d, Americans were indifferent I had that question on a test so it should be right and if you are having trouble with other courses I'd be obliged to help you.
Hope this helps.
Red: The color of blood and, therefore, of martyrdom. Worn on the feasts of martyrs as well as Palm Sunday, Pentecost, Good Friday and celebrations of Jesus Christ's passion.