Read the excerpt below, then answer the question.
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Elena gripped the edge of the podium. Her notes were neatly arranged, but her palms were slick with perspiration. Across the front row sat her mentor, Professor Vance, his face unreadable behind thick spectacles. When Elena paused before her final conclusion, Vance gave a single, firm nod. The subtle gesture released the knot in Elena's chest, allowing her voice to ring out with newfound conviction.
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Based on the excerpt, how does Professor Vance's nod affect Elena?
- AIt signals that her time has expired and she must finish immediately.
- BIt provides reassuring encouragement that restores her confidence.
- CIt indicates that he disagrees with her final conclusion.
- DIt causes her to feel embarrassed and lose her train of thought.