Brunner's gland is present in

Options

A. liver
B. duodenum
C. oesophagus
D. stomach.

Explanation

**Step-by-Step Solution:**

1. **Understanding Brunner's Gland**: Brunner's glands are specific types of glands that are classified as compound tubular glands. They are primarily responsible for producing a protective fluid.

2. **Location of Brunner's Gland**: These glands are located in the submucosa layer of the duodenum, which is the first part of the small intestine.

3. **Function of Brunner's Gland**: The main function of Brunner's glands is to secrete a mucoid fluid. This fluid serves to protect the duodenal mucosa from the acidic content that comes from the stomach.

4. **Analyzing the Options**:
- **Liver**: The liver is an organ and does not contain Brunner's glands.
- **Duodenum**: This is the correct answer, as Brunner's glands are specifically found here.
- **Esophagus**: The esophagus does not have Brunner's glands; it primarily produces mucus from its lining.
- **Stomach**: The stomach contains gastric glands, not Brunner's glands.

5. **Conclusion**: Based on the analysis of the options, the correct answer is that Brunner's glands are present in the duodenum.

**Final Answer**: Brunner's gland is present in the duodenum.

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