Read this excerpt from "The Tell-Tale Heart" by Edgar Allan Poe.

I knew that sound well, too. It was the beating of the old man’s heart. It increased my fury, as the beating of a drum stimulates the soldier into courage.

How does this incident provoke the narrator's decision to murder the old man?

The sound of the old man's heartbeat gives the narrator an additional reason to hate him.

The old man's heartbeat causes the narrator to recall his days as a soldier.

The narrator's headache is worsened by the sound of the old man's heartbeat.

The old man is being noisy on purpose, just to irritate the narrator.