Simplicity is an example of an abstract noun. It is because
an abstract noun is a word to describe something that a person can’t use any
sensory functions in which simplicity is a way of having to describe someone
without having to use any functions.
Is very simple, although the term "chaser" may not be as commonly used as it was when John Collier wrote his story. A chaser is a drink that is taken to follow the first alcoholic drink.
I believe the answer would be Rising action because the suspense (the "horrid" descriptions of the chamber) is slowly building up to the climax in which there would be a resolution to the conflict.
(I have read "The Cask of Amontillado" before)
Quietly would be your answer here