Explanation: When writing, an author can use several rhetorical devices in order to persuade, inform or impact the audience in the desired way. In the given options we can see four rhetorical devices: ethos is an appeal to the audience's ethics, logos is an appeal to the audience's logic and pathos is an appeal to the audience's emotions, and kairos is knowing what is most appropriate in a given situation. The given sentence from Dr. King's speech contains an example of pathos, because it is appealing to the audience's emotions.
