**Core Concept**
The sensory supply of the vocal cord involves the transmission of sensory information from the mucosa of the larynx to the central nervous system. This is crucial for the regulation of voice production, coughing, and swallowing.

**Why the Correct Answer is Right**
The correct answer is D. All of the above because the sensory supply of the vocal cord is provided by multiple nerves. The internal laryngeal nerve (A), a branch of the superior laryngeal nerve (C), supplies the mucosa of the laryngeal vestibule and the false vocal cords. The recurrent laryngeal nerve (B) supplies the mucosa of the true vocal cords, the arytenoid cartilages, and the posterior cricoarytenoid muscle. The convergence of sensory information from these nerves allows for the coordination of various laryngeal functions.

**Why Each Wrong Option is Incorrect**
* **Option A:** This choice is incorrect because while the internal laryngeal nerve does contribute to the sensory supply of the larynx, it only supplies the mucosa of the laryngeal vestibule and the false vocal cords, not the entire vocal cord.
* **Option B:** This choice is incorrect because while the recurrent laryngeal nerve supplies the mucosa of the true vocal cords, it is not the only nerve involved in the sensory supply of the vocal cord.
* **Option C:** This choice is incorrect because the superior laryngeal nerve supplies the mucosa of the laryngeal vestibule and the false vocal cords, but not the true vocal cords.

**Clinical Pearl / High-Yield Fact**
The convergence of sensory information from multiple nerves allows for the coordination of various laryngeal functions, such as voice production and coughing. This is essential for maintaining normal laryngeal function and preventing disorders such as vocal cord paralysis.

✓ Correct Answer: D. All of the above