Which of the following does not match?

Options

A. Pancreas-Largest exocrine gland
B. Antigen-Antibody
C. Thyroid-Goitre
D. Enzyme-Substrate

Answer

To solve the question "Which of the following does not match?", we need to analyze each option provided and identify the incorrect pair.

### Step-by-Step Solution:

1. **Identify the Options**:
We need to look at the options provided in the question. The options typically include pairs of terms that are related in some way.

2. **Analyze the First Option**:
- **Pancreas - Largest Exocrine Gland**:
The pancreas is indeed an exocrine gland, but it is not the largest. The liver is the largest exocrine gland in the body as it secretes bile through ducts.
- **Conclusion**: This pair is incorrect.

3. **Analyze the Second Option**:
- **Antigen - Antibody**:
Antigens are substances that induce an immune response, and antibodies are produced by the immune system to fight against these antigens.
- **Conclusion**: This pair is correct.

4. **Analyze the Third Option**:
- **Thyroid - Goiter**:
Goiter is an enlargement of the thyroid gland, often due to iodine deficiency.
- **Conclusion**: This pair is correct.

5. **Analyze the Fourth Option**:
- **Enzyme - Substrate**:
Enzymes are biological catalysts that act on substrates to facilitate biochemical reactions.
- **Conclusion**: This pair is correct.

6. **Final Conclusion**:
The only incorrect pair is the first option, where the pancreas is incorrectly stated as the largest exocrine gland. Therefore, the answer to the question is that the pair "Pancreas - Largest Exocrine Gland" does not match.

### Answer:
The incorrect pair is **Pancreas - Largest Exocrine Gland**.

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