Final answer:
The presence of character voice-over narration, particularly when introducing a flashback, does not mandate that the narration is 'restricted' and 'subjective'; it depends on whether it is first-person or third-person limited narration.
Step-by-step explanation:
The use of voice-over narration by a character, especially to introduce a flashback, does not automatically make the narration "restricted" and "subjective." While first-person narration provides a subjective viewpoint because it's told through one character's perspective using "I," "you," and "we," other narrative modes exist, such as third-person limited and omniscient narration. Third-person limited narration presents the story from one character's viewpoint, providing readers with a single character's thoughts and feelings, thus offering a limited perspective. However, third-person omniscient narration delivers a broader, more impartial perspective, not confined to one character's viewpoint. Therefore, the use of voice-over by a character can indeed be subjective if it is in the first-person, but if it's third-person limited, while it is restricted, it is not necessarily subjective as it doesn't involve the narrator's personal feelings or opinions.