**Core Concept**
Glucose absorption in the intestine is a critical process for maintaining blood glucose homeostasis. The intestinal absorption of glucose is facilitated by a specific transport mechanism that relies on the presence of sodium ions and the activity of a specific enzyme.

**Why the Correct Answer is Right**
Glucose absorption in the intestine occurs through the sodium-glucose cotransporter 1 (SGLT1) mechanism. This process involves the simultaneous transport of one sodium ion and one glucose molecule across the intestinal epithelial cells. The sodium gradient generated by the Na+/K+-ATPase pump creates an electrochemical gradient that drives the uptake of glucose into the intestinal cells. Once inside, glucose is then transported into the bloodstream via the glucose transporter 2 (GLUT2).

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the transport mechanism involved in glucose absorption. While glucose is absorbed in the intestine, the term "passive diffusion" is too general and does not accurately describe the sodium-glucose cotransporter 1 (SGLT1) mechanism.

**Option B:** This option is incorrect because it does not accurately describe the mechanism of glucose absorption in the intestine. The enzyme "sucrase" is involved in the breakdown of sucrose into glucose and fructose, but it is not directly involved in glucose absorption.

**Option C:** This option is incorrect because it does not accurately describe the mechanism of glucose absorption in the intestine. The enzyme "alpha-glucosidase" is involved in the breakdown of complex carbohydrates, but it is not directly involved in glucose absorption.

**Clinical Pearl / High-Yield Fact**
The sodium-glucose cotransporter 1 (SGLT1) is a high-affinity transporter that is responsible for the majority of glucose absorption in the intestine. This transporter is also the target of the medication canagliflozin, which is used to treat type 2 diabetes by inhibiting glucose reabsorption in the kidney.

**Correct Answer: D. Sodium-glucose cotransporter 1 (SGLT1).**