Answer: B) appeal to religion.
Step-by-step explanation: A rhetorical device is a literary tool that an author uses to inform or to persuade an audience, in order to do that, the author uses words in a certain way and employs a particular type of sentence structure, sound, or pattern of meaning. In the given sentence we can see an example of the use of a rhetorical device, in this case, an appeal to religion, as we can clearly see in the expression "so help us God."