Mark Twain used irony to illustrate the character of Miss Watson by contrasting her religious beliefs with her willingness to own slaves.
Irony is a figure of speech in which words are employed in such a way that their intended meaning is different from the actual meaning of the words. It may also be a situation that ends up in a different way than what is generally anticipated. To put it simply, it is a difference between appearance and reality.
The sentences that use rhetorical devices are: C) Outside, the torrential rain poured like a waterfall E) Saving the orangutans is a Herculean task for conservationists. The first sentence uses simile, and the second one a metaphor/allusion.