Select the correct inference of the given passage from "The Cask of Amontillado."
"You are not of the masons."
"Yes, yes," I said; "yes, yes."
"You? Impossible! A mason?"
"A mason," I replied.
"A sign," he said, "a sign."
"It is this," I answered, producing from beneath the folds of my roquelaire a trowel.
"You jest," he exclaimed, recoiling a few paces. "But let us proceed to the Amontillado."
"Be it so," I said, replacing the tool beneath the cloak and again offering him my arm.
Montresor is not a mason.
Fortunato is not a mason.
Fortunato does not believe that Montresor is a mason.
Montresor does not believe that Fortunato is a mason