Answer: B. Thyroarytenoid muscle
Step-by-step explanation:
The options include:
A. Epithelium
B. Thyroarytenoid muscle
C. Superficial layer of the lamina propria
D. Intermediate layer of the lamina propria
The cover-body theory of vocal fold vibration was published by Hurano in 1974 and he described the morphological structure of the vocal folds. He also divided them into the body and cover layer biomechanically.
The main substance of the vocal fold is regarded as the thyroarytenoid muscle. The muscle provides most of the mass of the vocal cord.