The most appropriate response to explain how a key literary element helps create the mood in the given paragraphs is:
The characterization of Madame Loisel helps create an exhilarated mood.
This choice is correct because the focus is on Madame Loisel's feelings of joy, success, and excitement, which are reflected in the vivid description of her experience at the ball. Her character is portrayed as being caught up in the thrill of the moment, contributing to an overall exhilarated mood.