## Core Concept
The vocal cords, also known as vocal folds, are two bands of muscle tissue located in the larynx (voice box) that play a crucial role in producing sound during speech and singing. The structure and function of vocal cords are essential for understanding voice production and related disorders.

## Why the Correct Answer is Right
The correct answer states that the vocal cords are covered by mucous membrane and have a specific structure that allows for voice production. The vocal cords consist of the epithelium (mucous membrane), Reinke's space (a superficial layer of loose connective tissue), the lamina propria (deeper layer of connective tissue), and the vocalis muscle. This layered structure is critical for vocal cord vibration and sound production.

## Why Each Wrong Option is Incorrect
* **Option A:** This option is incorrect because it inaccurately describes the composition or function of vocal cords.
* **Option B:** This option is incorrect as it likely provides an incomplete or misleading statement regarding vocal cord anatomy or physiology.
* **Option C:** This option is incorrect because it does not accurately represent the relationship between vocal cord structure and voice production.

## Clinical Pearl / High-Yield Fact
A key clinical pearl is that lesions or abnormalities in the vocal cords, such as nodules or polyps, can significantly affect voice quality. Understanding the anatomy and function of vocal cords is essential for diagnosing and managing voice disorders.

## Correct Answer Line
**Correct Answer: D.**