Which of the following is correct match :-

Options

A. Centrolecithal egg - insect
B. Megalecithal egg - eutherian mammals
C. Microlecithal egg - reptiles
D. Alecithal egg - birds

Answer

To solve the question regarding the correct match of eggs and their respective organisms, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Centrolacetal Egg**:
- A centrolacetal egg is characterized by having the yolk concentrated in the center of the egg.
- **Example**: Insects are known to have centrolacetal eggs.
- **Conclusion**: This match is correct.

2. **Understanding Megalacetal Egg**:
- A megalacetal egg contains a high amount of yolk.
- **Example**: This type of egg is typically found in reptiles and birds, not in eutherian mammals.
- **Conclusion**: The match of megalacetal egg with eutherian mammals is incorrect.

3. **Understanding Microlacetal Egg**:
- A microlacetal egg has a small amount of yolk.
- **Example**: This type of egg is found in marsupials and certain mammals.
- **Conclusion**: The match of microlacetal egg with reptiles is incorrect, as reptiles generally have megalacetal eggs.

4. **Understanding Alacetal Egg**:
- An alacetal egg is characterized by having little to no yolk.
- **Example**: This type of egg is mostly found in eutherian mammals.
- **Conclusion**: The match of alacetal egg with birds is incorrect, as birds typically have a high amount of yolk (megalacetal).

### Final Conclusion:
The only correct match from the options provided is:
- **Centrolacetal egg - Insect** (Option A).