Abductor of vocal cords is ?
**Core Concept**
The underlying principle being tested is the identification of the muscle responsible for abducted movement of the vocal cords, which is crucial for breathing. This involves knowledge of **laryngeal muscles** and their functions. The **recurrent laryngeal nerve** and **superior laryngeal nerve** play significant roles in controlling these muscles.
**Why the Correct Answer is Right**
The correct answer is related to the muscle that abducts the vocal cords, allowing for the widening of the glottis and facilitating inhalation. This action is primarily controlled by the **posterior cricoarytenoid muscle**, which is innervated by the **recurrent laryngeal nerve**. This muscle's action is essential for preventing the vocal cords from obstructing the airway during breathing.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it is not the primary abductor of the vocal cords.
**Option B:** Incorrect as it is not directly involved in the abduction of the vocal cords.
**Option C:** Incorrect because, although it is a laryngeal muscle, its function does not include abduction of the vocal cords.
**Clinical Pearl / High-Yield Fact**
Remembering that the **posterior cricoarytenoid muscle** is the only muscle to abduct the vocal cords is crucial for understanding respiratory physiology and managing conditions affecting the larynx. This knowledge is vital in clinical scenarios involving airway management.
**Correct Answer:** D. Posterior cricoarytenoid muscle.