Okay, so people need to see the paragraph first then, based on context clues and her feelings she expresses in the paragraph, then conclude the answer.
I think that the subject of the excerpt is c) Mathilde's discontent with her humble lifestyle because she compared her life to a rich one, one she felt that she was meant to have.
More information please :)
Based on the sentences from ‘The Cask of Amontillado’, the
literary technique that is employed in the sentence is foreshadowing. This is a
way of having a writer or author give its reader an idea of what would likely
occur later on.