The correct answer is The simile helps the reader understand King Arthur's pain.
Explanation:
The text "Morte d'Arthur" is a poem that refers to King Arthur's death. In this, the author describes Arthur's feelings, thoughts, and words as he dies. For example, in the line presented the author describes how King Arthurs had trouble breathing due to pain. Moreover, in this, the author compares these to a nightmare that allows the reader to better understand the King's pain. Besides this, the literary figure is a simile because the comparison includes the word "like", which is used in simile but not in metaphor.
