Select what is not true of intestinal villi among followings.

Options

A. (a) They possess microvilli
B. (b) They increase the surface area
C. (c) They are supplied with capillaries and the lacteal vessels
D. (d) They only participate in digestion of fats

Answer

To determine which statement is not true about intestinal villi, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Intestinal Villi**:
- Intestinal villi are small, finger-like projections that line the inner surface of the small intestine. Their primary function is to increase the surface area for absorption of nutrients.

2. **Analyzing Option A**:
- **Statement**: "They possess microvilli."
- **Evaluation**: This statement is true. Intestinal villi have microvilli on their surface, which further increases the surface area for absorption.

3. **Analyzing Option B**:
- **Statement**: "They increase the surface area."
- **Evaluation**: This statement is also true. The presence of villi and microvilli significantly enhances the surface area of the small intestine, facilitating better absorption of nutrients.

4. **Analyzing Option C**:
- **Statement**: "They are supplied with capillaries and lacteal vessels."
- **Evaluation**: This statement is true as well. Villi contain capillaries that absorb nutrients into the bloodstream and lacteal vessels that absorb fats and fat-soluble vitamins into the lymphatic system.

5. **Analyzing Option D**:
- **Statement**: "They only participate in digestion of fats."
- **Evaluation**: This statement is false. While intestinal villi do play a role in the digestion of fats, they are also involved in the digestion and absorption of carbohydrates and proteins, as well as secretion and immune defense functions.

6. **Conclusion**:
- The statement that is not true about intestinal villi is option D: "They only participate in digestion of fats."

### Final Answer:
**D: They only participate in digestion of fats.**