**Core Concept**
A laryngocele is a rare congenital or acquired lesion that involves herniation of the laryngeal mucosa through a weakened area of the laryngeal cartilages, specifically through the saccule of the laryngeal ventricle. This condition is often associated with increased pressure within the laryngeal ventricle.

**Why the Correct Answer is Right**
The correct answer is the thyroepiglottic membrane, which is a weak area in the larynx where the herniation occurs. The thyroepiglottic membrane is a fibrous structure that connects the thyroid cartilage to the epiglottis. The laryngeal saccule, which is a small pouch-like structure, extends from the anterior part of the laryngeal ventricle and passes through the thyroepiglottic membrane. Herniation of the laryngeal mucosa through this membrane leads to the formation of a laryngocele.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because the cricovocal membrane is not a known site for laryngocele formation. The cricovocal membrane is a fibrous structure that connects the cricoid cartilage to the vocal process of the arytenoid cartilage.
* **Option B:** This option is incorrect because the arytenoepiglottic membrane is not a known site for laryngocele formation. The arytenoepiglottic membrane is a fibrous structure that connects the arytenoid cartilage to the epiglottis.
* **Option D:** This option is incorrect because the thyrohyoid membrane is not a known site for laryngocele formation. The thyrohyoid membrane is a fibrous structure that connects the thyroid cartilage to the hyoid bone.

**Clinical Pearl / High-Yield Fact**
Laryngoceles can cause symptoms such as a voice change, difficulty swallowing, and shortness of breath. They can also increase the risk of aspiration and respiratory obstruction.

**Correct Answer: C. Thyroepiglottic membrane**