When you use imagery in poetry it helps you to visualize it more or better.
Visual effect of poetry.
B. It states that they are "alone together" and an oxymoron is two contradictory terms placed together.
Because people are fake, rude, two-faced, and toxic. It's a place where people can get a chance to get their feelings out to a perosn behind the screen because they think they can get away with it. It's sickening.
B. it is an English sonnet