Which sentence from the story BEST indicates the unreliability of the narrator?
A. "I was never kinder to the old man than during the whole week before I killed him. "
B. "To think that there I was, opening the door, little by little, and he not even to dream of my secret deeds or thoughts."
C. "No doubt I now grew very pale; – but I talked more fluently, and with a heightened voice. "
D. "I swung the chair upon which I had been sitting, and grated it upon the boards, but the noise arose over all and continually increased."