Answer: C) She is the only person who is late on the day of the lottery.
Even before we know who was selected in the lottery, the author sets Tessie Hutchinson apart by telling us that she arrived late. She claims to have forgotten what day it was. This is markedly different to the rest of the villagers, as the lottery is the most important institution of the community, and it is inconceivable that someone could have forgotten about it. This "freedom" of mind that allows her to forget about the lottery sets her apart from everyone else in the village.