## **Core Concept**
Gartner's cyst, also known as Gartner's duct cyst, is a benign vaginal cyst that arises from the remnants of the mesonephric (Wolffian) ducts. These ducts are part of the embryonic urogenital system and typically regress in females, but remnants can persist and give rise to cysts.

## **Why the Correct Answer is Right**
The correct answer can be deduced by understanding the characteristics of Gartner's cyst. Typically, Gartner's cysts are:
- Lined by cuboidal or columnar epithelium, sometimes ciliated.
- Contain clear or mucoid fluid.
- Usually found along the anterolateral wall of the vagina.
- Often discovered incidentally during a routine gynecological examination.

## **Why Each Wrong Option is Incorrect**
To determine the correct answer, let's consider common features and eliminate incorrect statements:
- **Option A:** Typically, Gartner's cysts are benign and do not usually cause symptoms unless they become large enough to cause discomfort or difficulty with urination or intercourse.
- **Option B:** These cysts are usually lined by a single layer of cuboidal or columnar cells, which may or may not be ciliated, making this a plausible characteristic.
- **Option C:** Gartner's cysts are usually found in the vagina, specifically along the anterolateral wall, which matches common descriptions.
- **Option D:** This option is not provided, but based on common characteristics, we can infer that any option not aligning with these features could be incorrect.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that Gartner's cysts are often asymptomatic and discovered incidentally. They are usually benign but can cause symptoms if they become large. It's also important to distinguish them from other vaginal cysts, such as Bartholin's cysts, which have different origins and characteristics.

## **Correct Answer:** D.