**Cells of Peritoneum comprise:**

The correct answer is option 'D' - Squamous Epithelium.

**Explanation:**

The peritoneum is the serous membrane that lines the abdominal cavity and covers the organs within it. It is composed of a single layer of cells called mesothelial cells, which are a type of epithelial cells. These cells play a crucial role in the function and protection of the peritoneum.

The peritoneal mesothelium can be classified into two types based on the morphology of its cells:

1. **Simple Squamous Epithelium**: The majority of the mesothelial cells in the peritoneum are thin and flat, resembling a squamous shape. Squamous epithelium is composed of a single layer of flat cells that are tightly packed together. These cells have a flattened nucleus and are involved in various functions such as lubrication, absorption, and secretion.

2. **Simple Cuboidal/Cuboidal Columnar Epithelium**: In some areas of the peritoneum, the mesothelial cells may appear cuboidal or columnar in shape. Cuboidal epithelium consists of cube-shaped cells, while columnar epithelium consists of taller, elongated cells. These cells may be found in regions where active secretion or absorption takes place.

While options 'A' (Ciliated Epithelium) and 'B' (Glandular Epithelium) are types of epithelial tissues found in other parts of the body, they are not typically present in the peritoneum. The peritoneum primarily consists of simple squamous epithelium, which is well-suited for its protective and lubricating functions.

In summary, the cells of the peritoneum comprise a simple squamous epithelium, which is responsible for maintaining the integrity and function of this serous membrane.

Squamous epithelium .....ex:-mesothelium of body cavities(pleura,peritoneum,and pericardium),wall of Bowman's capsule, alveoli in lungs,retina of eye,endothelium of blood vessels.......