Answer:
Mainly Trench Warfare was popularized by the use of new mechanized weapons such as Artillery, and also because of the mass victories in the east on germany's side, Russia used these as a form of slowing them down and to protect their troops, but often these trenches hurt these men by disease, starvation, etc.
I think your best shot is probably choice A
I'm sorry if this isn't right but from what I learned it's the first one :)
<span>Samuel Cooper and </span><span>Rober E Lee - Confederates
</span><span>Ulysses S Grant - Union </span>
There was so many casualties because enemies invaded malls,homes and others and the people didn't have enough time to evacuate.
