Which of the following statements about whispered speech is accurate?

• A. It is produced by approximating the arytenoid cartilages so that their medial surfaces are in direct contact.
• B. Spectrographic analysis of whispered speech reveals no discernible formants for the vowels.
• C. It is composed largely of aperiodic sounds.
• D. Most people can produce longer utterances per breath using whispered speech than they can using conventional phonation.

Answer: (C)

Whispered speech relies on turbulent airflow through a constriction rather than on vibrating vocal folds. Because there’s no periodic glottal pulse to set up a regular harmonic series, the sound energy is broad-band and aperiodic. That makes the statement describing whispered speech as largely aperiodic the best description.

Think of it this way: voiced speech shines with a clear pitch and strong formant patterns because the vocal folds vibrate and excite the vocal tract’s resonances. Whispering changes the source to noise-like energy, so the overall signal is more noise than a clean, periodic wave. The other ideas don’t fit as well: whispering doesn’t require the arytenoid cartilages to press together to create voicing, formants can still appear in whispered vowels (they’re just less pronounced), and whispering typically isn’t more breath-efficient for longer utterances than voiced speech.