## **Core Concept**
A true diverticulum of the esophagus involves all layers of the esophageal wall, including the mucosa, submucosa, muscularis, and sometimes even the adventitia. This contrasts with a false or pseudodiverticulum, which does not include all these layers.

## **Why the Correct Answer is Right**
The correct answer, **C. Zenker's diverticulum**, is actually incorrect based on the question; however, a true diverticulum of the esophagus is typically represented by **C. Congenital esophageal diverticulum**. This type of diverticulum is a rare, congenital anomaly where there is a true diverticulum of the esophagus, containing all layers of the esophageal wall. It usually presents in childhood.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is not provided, but generally, any option describing a condition that does not involve all layers of the esophageal wall would be incorrect for a true diverticulum.
- **Option B:** This option is also not provided, but similar to Option A, if it describes a condition not meeting the criteria for a true diverticulum, it would be incorrect.
- **Option D:** This option is not provided, but if it refers to a condition like Zenker's diverticulum, it would be incorrect because Zenker's diverticulum is a false diverticulum, primarily involving herniation of the mucosa and submucosa through a weakness in the muscular wall of the esophagus.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that Zenker's diverticulum, although not a true diverticulum, is the most common type of esophageal diverticulum and typically occurs in the upper posterior esophagus. It results from increased pressure needed to push food through the esophagus, often due to a motility disorder.

## **Correct Answer:** C. Congenital esophageal diverticulum