Which statement about unilateral vocal fold paralysis is true?

• A. A patient cannot produce a normal voice.
• B. A patient may be able to produce a normal voice if the non-paralyzed vocal fold achieves complete glottic closure.
• C. A patient always produces a normal voice.
• D. Unilateral paralysis has no effect on voice.

Answer: (B)

Phonation relies on complete closure of the vocal folds to build up subglottal pressure and produce a steady, efficient voice. When one vocal fold is paralyzed, it often can’t move to the midline, creating a gap and giving a breathy or rough voice. But if the non-paralyzed vocal fold can move enough to achieve complete glottic closure, the glottis can close properly during vibration, allowing normal phonation to occur in at least some cases. That’s why this statement is true: a normal voice can be produced when the healthy fold achieves full closure against the paralyzed fold. The other options are too absolute or false because unilateral paralysis does not always eliminate normal voice, does not always preserve it, and does affect voice quality.