Final answer:
A broken mirror can be a method of foreshadowing something bad happening in a story.
Step-by-step explanation:
A plot detail that might be a method of foreshadowing that something bad will happen is option D, a broken mirror. In literature, a broken mirror is often seen as a symbol of bad luck or a precursor to unfortunate events. By including this detail in a story, the author hints at the possibility of something negative occurring.
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