Read this passage from "The Raven" by Edgar Allan Poe. Open here I flung the shutter, when, with many a flirt and flutter,
In there stepped a stately Raven of the saintly days of yore.
Not the least obeisance made he; not a minute stopped or stayed he;
But, with mien of lord or lady, perched above my chamber door—
Perched upon a bust of Pallas just above my chamber door—
Perched, and sat, and nothing more.

How does the appearance of the raven propel the narrative action of the story?

A. It introduces a new character who befriends the speaker and helps him search for Lenore.

B. The appearance of the raven creates the exposition of the poem, providing readers background about the speaker.

C. It suggests that the raven creates a parallel between the action of the poem and Greek mythology.

D. It introduces a new character by which readers are able to gauge the speaker's deteriorating mental state.