The absorption of monosaccharide such as glucose in the small intestine occurs by :

Options

A. Simple diffusion method
B. Facilitated transport method
C. Active transport method
D. All of the above mention methods

Answer

To solve the question regarding the absorption of monosaccharides such as glucose in the small intestine, we can analyze the different methods of absorption mentioned in the options.

### Step-by-Step Solution:

1. **Understanding Monosaccharide Absorption**:
- Monosaccharides like glucose are simple sugars that need to be absorbed efficiently in the small intestine for energy.

2. **Evaluating the First Option: Simple Diffusion**:
- Simple diffusion is a process where molecules move from an area of higher concentration to an area of lower concentration without the need for energy.
- While glucose can be absorbed through simple diffusion, this method is not the primary mechanism for glucose absorption in the small intestine.

3. **Evaluating the Second Option: Facilitated Transport**:
- Facilitated transport involves the use of carrier proteins that help transport glucose across the cell membrane.
- This process does not require energy and allows glucose to move down its concentration gradient, making it a significant method of absorption for glucose.

4. **Evaluating the Third Option: Active Transport**:
- Active transport is a process that requires energy (usually from ATP) to move substances against their concentration gradient (from low to high concentration).
- Glucose is absorbed in the small intestine through active transport, particularly via the sodium-glucose transport proteins (SGLT), which utilize the sodium gradient to help transport glucose into the cells.

5. **Conclusion**:
- Since glucose can be absorbed through simple diffusion, facilitated transport, and active transport, all these methods are involved in the absorption process.
- Therefore, the correct answer to the question is that the absorption of monosaccharides such as glucose in the small intestine occurs by **all of the above methods**.

### Final Answer:
**All of the above methods (Simple diffusion, Facilitated transport, Active transport)**