Which excerpt from "the cask of amontillado" best illustrates the sarcastic tone of the narrator?

a"come," i said, with decision, "we will go back; your health is precious. you are rich, respected, admired, beloved; you are happy, as once i was. you are a man to be missed. for me it is no matter.
b. in an instant he had reached the extremity of the niche, and finding his progress arrested by the rock, stood stupidly bewildered. a moment more and i had fettered him to the granite.
c."let us go, nevertheless. the cold is merely nothing. amontillado! you have been imposed upon. and as for luchresi, he cannot distinguish sherry from amontillado."
d. in painting and gemmary, fortunato, like his countrymen, was a quack, but in the matter of old wines he was sincere.