The most accurate response regarding the tone of a story is:
It should be tied directly to the theme.
Tone helps to convey the underlying message or theme of the story, enhancing the reader's understanding and emotional response. While consistency in tone can be important, tone can also evolve throughout the story to reflect changes in the narrative or characters. Creating suspense, while effective, is not a requirement for tone, and a sudden shift in tone may or may not be appropriate depending on the story.