**Core Concept**
The vitreous humor is a clear gel-like substance that fills the space between the lens and the retina in the eye. It is composed of water, glycoproteins, and other components, including collagen. The type of collagen found in the vitreous humor is crucial for maintaining its structure and transparency.

**Why the Correct Answer is Right**
The vitreous humor contains a type of collagen known as type II collagen. This type of collagen is a major component of cartilage, but it is also found in the vitreous humor, where it helps to maintain its gel-like structure. The type II collagen in the vitreous humor is composed of a specific amino acid sequence that allows it to form a network of fibers, which gives the vitreous humor its characteristic gel-like consistency.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because type I collagen is primarily found in skin, bones, and tendons, and is not a major component of the vitreous humor.
**Option B:** This option is incorrect because type III collagen is primarily found in blood vessels and is not a major component of the vitreous humor.
**Option C:** This option is incorrect because type IV collagen is primarily found in basement membranes and is not a major component of the vitreous humor.

**Clinical Pearl / High-Yield Fact**
The vitreous humor is a unique structure that is composed of a combination of collagen and glycoproteins. Understanding the type of collagen found in the vitreous humor is important for diagnosing and treating conditions such as vitreous detachment and retinal tears.

**Correct Answer:** C. Type II collagen.