The rhetorical device that <span>is used in this excerpt from Mark Twain's "The Danger of Lying in Bed" is anecdote (assuming that your options are allusion, rhetorical question, anecdote, and logic). There is no allusion to any other text here, so that is not the correct answer. There are also no rhetorical questions - questions that don't need an answer because it is implied. I guess there is logic, but it is not a rhetorical device really. So, I'd choose anecdote, because an anecdote is a short, interesting story from someone's life, as is the case here.</span>
The prologue's lines foreshadow the story's main plot: a tragedy between star crossed lovers. It revolves mainly around civil blood and how it will make the civil hands' unclean which is the main 'clue' of the ending of the story which is death.
I would say that the principle means of characterization employed by the author is dialogue. Since Romeo and Juliet is a play, everything we know actually comes from the conversations, be it a dialogue, or a monologue.
