Which of the following proteins is identified as fibrous?

Collagen is classified as a fibrous protein due to its structural role in the body. Fibrous proteins are usually long, narrow, and insoluble in water, contributing to the strength and support of various tissues. Collagen is the primary structural protein found in connective tissues such as tendons, ligaments, skin, and cartilage. It provides tensile strength and structural integrity to these tissues, which is essential for their function.

In contrast, hemoglobin and myoglobin are globular proteins, which means they tend to be soluble and have more spherical shapes. They function primarily in oxygen transport and storage and do not serve the structural roles characteristic of fibrous proteins. Enzymes are also primarily globular proteins, designed for catalyzing biochemical reactions rather than providing structural support. Collagen's unique triple helix structure and its ability to form fibrils is what distinguishes it as a fibrous protein and emphasizes its role in providing mechanical strength to tissues.