The brush border of Malpighian tubules is found in 

Options

A. inner surface of unilayered glandular epithelium
B. outer surface of unilayered glandular epithelium
C. outer surface of multilayered absorpture epithelium
D. inner surface of multilayered absorpture epithelium

Answer

To solve the question regarding the location of the brush border of Malpighian tubules, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure**: The brush border refers to the microvilli-covered surface that increases the surface area of epithelial cells. This structure is crucial for enhancing absorption.

2. **Identify the Function**: The primary function of the brush border in Malpighian tubules is to facilitate absorption. The increased surface area allows for more efficient absorption of substances.

3. **Know the Epithelium Type**: The brush border is typically associated with simple cuboidal or simple columnar epithelium. In the case of Malpighian tubules, these are lined with a specialized type of epithelium that has a brush border.

4. **Analyze the Options**: The question provides four options regarding where the brush border is located:
- Option 1: Inner surface of unilayered glandular epithelium
- Option 2: Outer surface of unilayered glandular epithelium
- Option 3: Outer surface of multilayered absorptive epithelium
- Option 4: Inner surface of multilayered absorptive epithelium

5. **Evaluate Each Option**:
- **Option 1**: Incorrect, as the brush border is not found on the inner surface of unilayered glandular epithelium.
- **Option 2**: Correct, as the brush border is found on the outer surface of unilayered glandular epithelium.
- **Option 3**: Incorrect, as the brush border is not found on the outer surface of multilayered absorptive epithelium.
- **Option 4**: Incorrect, as the brush border is not found on the inner surface of multilayered absorptive epithelium.

6. **Conclusion**: Based on the analysis, the brush border of Malpighian tubules is found on the outer surface of unilayered glandular epithelium.

### Final Answer:
The brush border of Malpighian tubules is found in the **outer surface of unilayered glandular epithelium**.

---