Could you show me a example of it
I say it's B but I might be wrong
A Simile. This is because it is comparing the muck to a leech using the words "as if".
d. when the audience knows something that the characters in the play do not
Dramatic irony occurs when the audience, readers or listeners knows something that the characters do not. It is a literary device wherein the audience's comprehension of the work surpasses that of the character's understandings. It is a form of irony contrary to that of a verbal irony because the irony of this type is embedded or can be found within the work's structure and not on its words. Though dramatic irony is usually seen in theaters, it can also be used and witness in performing arts.