C. A manuscript. If only one answer is allowed. A primary source is a document that is created at the time in which the events it describes is occurring. A manuscript is something that is written by hand and therefore the author would be describing events or ideas that occurring at the time of creating the manuscript. A textbook references other ideas and is a secondary source. A fiction book describes unreal events. A journal article is published in a collection and often refers to other previous events.
The setting in this poem includes both time and place. The author first gives us a sense of both mood and time with the first line:
"Once upon a midnight dreary,"
We as readers are then told that the author/narrator is in his study, as evidence is given of the books, the bust of Pallas, and the other ecoutrements that lend themselves to studious labors. We are certain that this is, at the very least, a room, as Poe refers to his "chamber door" multiple times throughout the poem. In closing, we can conclude that this poem is set in the 1800s, on a dark and stormy night, in the author's place of academic study and leisure.
C. Juliet expresses her fear that the promises made between her and Romeo will not last.