Secretin stimulates the activity of :

Options

A. Liver
B. Gastric gland
C. Pancreas
D. Gall-bladder

Answer

### Step-by-Step Solution:

1. **Understanding Secretin**: Secretin is a hormone that is secreted by the enteroendocrine cells in the gastrointestinal tract, particularly in the duodenum.

2. **Identifying the Target Organs**: Secretin primarily targets the pancreas, liver, and gallbladder. It plays a significant role in regulating the digestive process.

3. **Function of Secretin**: The main function of secretin is to stimulate the pancreas to secrete bicarbonate ions and water. This helps to neutralize the acidity of the chyme that comes from the stomach into the small intestine.

4. **Analyzing the Options**: The question provides options: liver, gastric gland, pancreas, and gallbladder. We need to identify which of these is primarily stimulated by secretin.

5. **Correct Answer**: Among the given options, secretin specifically stimulates the activity of the pancreas, which is responsible for producing digestive enzymes and bicarbonate.

6. **Conclusion**: Therefore, the correct answer to the question "Secretin stimulates the activity of:" is the pancreas.

### Final Answer:
Secretin stimulates the activity of the pancreas.

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