It is impossible to say how first the idea entered my brain; but once conceived, it haunted me day and night. Object there was none. Passion there was none. I loved the old man. He had never wronged me. He had never given me insult. For his gold I had no desire. I think it was his eye! yes, it was this! He had the eye of a vulture—a pale blue eye, with a film over it. Whenever it fell upon me, my blood ran cold; and so by degrees—very gradually—I made up my mind to take the life of the old man, and thus rid myself of the eye forever. –“The Tell-Tale Heart,”
Edgar Allan Poe

Which statement best explains how a reader can tell that the passage’s narrator is unreliable?

The narrator says he loved the old man, but other events show he is prejudiced against older people.
The narrator claims he is not suffering from madness, but he has no rational reason to kill the old man.
The narrator insists he is uninterested in gold, but he clearly murdered the man for his money.
The narrator says he does not know where he got the idea to kill the old man, but he is lying to protect someone else.