What new technology most changed the way people on the home front understood the civil war?

a.) ironclad ships
b.) submarines
c.) photography
d.) the telegraph

I'm going to take a gander here and say C.)

Newspapers were a huge thing back then and with the addition of photographs i'm sure that people at home were able to see what the battlefields looked like.

The transcontinental railroad provided a means of fast transportation. it cut a 6 month trip into 6 days, created jobs for many people and encouraged immigration. the homestead act played a huge role in western expansion; it allowed settlers to begin a fresh start, and gave them land in exchange for their residence for up to five years and a small fee.