Final answer:
The primary characters in a story are introduced during the exposition.
Step-by-step explanation:
The correct answer is C. exposition. The exposition is the introduction of the story where the primary characters are introduced along with the setting and the initial conflict. It provides background information and sets the stage for the rest of the story. For example, in the story 'Harry Potter and the Sorcerer's Stone,' the exposition introduces Harry Potter, Hermione Granger, and Ron Weasley as the primary characters.
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