Answer:
The text is accentuated in Italics to emphasis the importance of the text and the sound narrator is hearing.
The narrator percieves the sound to be a sound of an old man's heartbeat.
The sound was the narrator's own heartbeat.
Explanation:
'The Tell Tale Heart' is a short story written by Edgar Allan Poe. The story is about an unnamed narrator who cunningly plots a murder of an old man with vulture eye and murders him.
In lines 170-178, the narrator describes the sound that he is hearing, which is accentuated in Italics. The text is accentuated in italics to emphasis on the importance of the text. The narrator is <em>'low, dull, quick sound...' </em>This sound, narrator percives to be of an old man's heartbeat, whom the narrator had brutallly murdered.
In reality, the sound that narrator is hearing was of his own heartbeat. The narrator who claims to be sane even after committing the crime of murder begins to be nervous about his crime.
