The final line of the excerpt from John Keats's "Ode on Melancholy" is an example of **metaphor**. A metaphor is a figure of speech that compares two things without using the words "like" or "as." In this case, Keats compares the speaker's sorrow to a hungry animal that is feeding on the beauty of the morning rose. This comparison helps the reader to understand the speaker's feelings of sadness and despair.
The other options are not correct. Option B, rhyming couplet, is a pair of lines in a poem that rhyme with each other. The final line of the excerpt does not rhyme with any other line in the excerpt. Option C, simile, is a figure of speech that compares two things using the words "like" or "as." The final line of the excerpt does not use the words "like" or "as." Option D, repetition, is the use of the same word or phrase multiple times in a row. The final line of the excerpt does not repeat any words or phrases.
Here is a more detailed explanation of why the final line of the excerpt is an example of a metaphor:
* The speaker does not say that his sorrow is **like** a hungry animal. He says that it **is** a hungry animal.
* The comparison between the speaker's sorrow and a hungry animal helps the reader to understand the speaker's feelings of sadness and despair.
* The comparison is not literal, but it is still effective in conveying the speaker's feelings.