I believe it is A, semicolons as it separates the the thoughts as you're reading.
The effects of the Great Chicago fire would be the most focused because it is an exact topic focused on and exact event. The others could all be narrowed down.
Here is a website for meaningful poems. I think you can find a good one on here. I couldn't really find a clean meaningful rap song so I tried to find a poem, but I don't know what kind of thing you like so here you go, https://classicalpoets.org/2016/01/07/10-greatest-poems-ever-written/
