Select the correct inference of the given passage from "the cask of amontillado."

"my friend, no. it is not the engagement, but the severe cold with which i perceive you are afflicted. the vaults are insufferably damp. they are encrusted with nitre." (4 points)

the narrator wants fortunato to think he is concerned for his health.
the narrator wants to make up another reason for fortunato to avoid the vaults.
the narrator doesn't want to catch a cold in the vaults.
the narrator knows the vaults are damp and covered in nitre