Because they reflect historians points of view most important events. Hope this helped <3
An electronic calendar would be an example of software. The remaining things which you've mentioned in your questions would be examples of peripheral devices (so mouse, scanner, and monitor :)).
“The land was mined
territory and was subject to artillery, shelling, and gunfire” made it most difficult
for soldiers to cross the area between the trenches.
The correct answer between all
the choices given is the last choice or letter D. I am hoping that this answer
has satisfied your query and it will be able to help you in your endeavor, and
if you would like, feel free to ask another question.