**Core Concept**
Fructose transport across cell membranes is a crucial process for glucose homeostasis, particularly in the small intestine and liver. The primary fructose transporter is a facilitative diffusion protein that allows fructose to move down its concentration gradient.

**Why the Correct Answer is Right**
The primary fructose transporter is **GLUT5**. It is a member of the solute carrier family 2 (SLC2), specifically SLC2A5, and is predominantly expressed in the small intestine, where it plays a key role in fructose absorption. GLUT5 has a high affinity for fructose and a low affinity for glucose, making it an efficient transporter for fructose uptake.

**Why Each Wrong Option is Incorrect**
**Option A:** is incorrect because it is a general term for glucose transporters, not specifically related to fructose.
**Option B:** is incorrect because it is a sodium-glucose cotransporter, which is primarily involved in glucose absorption in the small intestine.
**Option C:** is incorrect because it is a monocarboxylate transporter, which is involved in the transport of lactate, pyruvate, and other monocarboxylates.

**Clinical Pearl / High-Yield Fact**
Glucose and fructose absorption in the small intestine is a crucial process for glucose homeostasis. Defects in GLUT5 expression or function can lead to fructose malabsorption, which can cause symptoms such as bloating, gas, and diarrhea.

**Correct Answer:** C. GLUT5