Hello there,
The line from the story that reveals Montresor's true intentions would be option C: "I had finished a portion of the last and the eleventh; there remained but a single stone to be fitted and plastered in."
Hope this helps and have a great day :)
Hope this helps but I think the answer is B.
The answer is b because prefix comes before, suffix comes after, and a synonym is a word that is like another word