A. I was never kinder to the old man than during the whole week before I killed him.
Explanation:
This sentence indicates the state of mind that the narrator found himself in. We can see that the behaviour and attitudes of the narrator are not normal. He tells us that he had already planned to kill the old man, and despite this, he was much kinder to him than before. This passage indicates that the man does not have a healthy mind, and leads us to think that he will most likely be an unreliable narrator.
