Eggs of birds are

Options

A. Microlecithal
B. Centrolecithal
C. Megalectithal
D. Alecithal

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the type of eggs produced by birds. We need to identify the correct classification among the given options: microlacetal, centrolacetal, megalacetal, or alacetal.

2. **Identifying Egg Characteristics**: Bird eggs are characterized by a high content of yolk. This is a crucial point because the classification of eggs is often based on the amount and distribution of yolk.

3. **Classifying the Egg Type**:
- **Microlacetal**: This type indicates a small amount of yolk compared to the cytoplasm. This does not apply to bird eggs.
- **Centrolacetal**: This type indicates that the yolk is centrally located within the egg. This is also not applicable to bird eggs.
- **Megalacetal**: This type indicates a large amount of yolk. Bird eggs fall into this category due to their high yolk content.
- **Alacetal**: This indicates negligible yolk content, which again does not apply to bird eggs.

4. **Further Classification**:
- Bird eggs are not only megalacetal but also **telolacetal**, meaning the yolk is concentrated at one pole of the egg, and **cleidoic**, indicating the presence of a calcium carbonate shell.

5. **Conclusion**: Based on the characteristics and classifications discussed, the correct answer is that bird eggs are **megalacetal**.

### Final Answer:
Bird eggs are **megalacetal**.

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