Perichondrium is white fibrous connective tissue. The perichondrium is a layer of dense irregular connective tissue, which surrounds the cartilage of developing bone. It consists of two separate layers namely, an outer fibrous layer and inner chondrogenic layer. The fibrous layer contains fibroblasts, which produce collagenous fibers. The chondrogenic layer remains undifferentiated and can form chondrobasts or chondrocytes. It also functions in the growth and repair of cartilage. Hence, the correct answer is option 'B'.

Perichondrium is a white fibrous connective tissue that surrounds cartilage in the body. It plays a crucial role in maintaining the structure and function of cartilage.

Structure:
The perichondrium consists of two layers - an outer fibrous layer and an inner cellular layer.

1. Outer fibrous layer: This layer is made up of dense irregular connective tissue. It contains collagen fibers, which provide strength and support to the perichondrium.

2. Inner cellular layer: This layer is composed of fibroblasts and chondroblasts. Fibroblasts are responsible for producing collagen fibers, while chondroblasts are responsible for producing cartilage matrix.

Function:
The perichondrium serves several important functions in relation to cartilage:

1. Protection: The outer fibrous layer of the perichondrium provides protection to the underlying cartilage by acting as a physical barrier against mechanical stress and injury.

2. Nutrition: The perichondrium contains blood vessels that supply nutrients to the avascular cartilage. These blood vessels penetrate the perichondrium and reach the outermost layer of cartilage, allowing for nutrient exchange.

3. Growth and Repair: The inner cellular layer of the perichondrium contains chondroblasts, which are responsible for the growth and repair of cartilage. Chondroblasts produce new cartilage matrix, which contributes to the expansion and maintenance of cartilage tissue.

4. Attachment: The perichondrium helps to attach cartilage to surrounding tissues, such as bone or other connective tissues. It forms a smooth interface between the cartilage and other tissues, allowing for smooth movement and reducing friction.

5. Differentiation: In some cases, the perichondrium can differentiate into osteoblasts, which are responsible for bone formation. This process is important during endochondral ossification, where cartilage is replaced by bone during skeletal development.

Overall, the perichondrium is essential for the growth, maintenance, and repair of cartilage in the body. Its fibrous outer layer provides protection, while its inner cellular layer contributes to cartilage growth and repair.