**Core Concept**
The triple helix structure is a unique arrangement of amino acids found in certain proteins, characterized by the coiling of three polypeptide chains. This specific conformation is a hallmark of a particular type of collagen, which is a major component of connective tissue in the body.

**Why the Correct Answer is Right**
Collagen is a type of fibrous protein that provides structural support to various tissues, including skin, bones, tendons, and ligaments. The triple helix structure of collagen is formed by the coiling of three alpha-helices, each composed of amino acids that are rich in glycine and proline. This unique arrangement allows collagen to provide great tensile strength and elasticity to connective tissue. The triple helix structure of collagen is stabilized by hydrogen bonds between the amino acids, which contribute to its remarkable mechanical properties.

**Why Each Wrong Option is Incorrect**
**Option A:** Cystine is a disulfide-linked dimer of cysteine residues and does not exhibit a triple helix structure.
**Option C:** Pectin is a type of polysaccharide found in plant cell walls and does not have a triple helix structure.
**Option D:** DNA is a double-stranded helix, not a triple helix, and is composed of nucleotides rather than amino acids.

**Clinical Pearl / High-Yield Fact**
The triple helix structure of collagen is highly susceptible to damage from enzymatic degradation by collagenases, which can lead to conditions such as osteoarthritis and rheumatoid arthritis. Understanding the unique properties of collagen is crucial for developing effective treatments for these diseases.

✓ Correct Answer: B. Collagen