In Gymnosperm which is not found:-

Options

A. Antheridia
B. Archegonia
C. Both
D. None of these

Answer

To solve the question regarding what is not found in Gymnosperms, we will analyze the options provided and understand the characteristics of Gymnosperms.

### Step-by-Step Solution:

1. **Understanding Gymnosperms**:
- Gymnosperms are a group of seed-producing plants that include conifers, cycads, Ginkgo, and gnetophytes. They are characterized by having seeds that are not enclosed in an ovary (unlike angiosperms).

2. **Identifying Key Structures**:
- **Archegonia**: These are female reproductive structures that produce eggs. Gymnosperms do have archegonia.
- **Antheridia**: These are male reproductive structures that produce sperm. Gymnosperms also have antheridia.
- **Threidia**: This term is not commonly associated with Gymnosperms and is likely a distractor in this context.

3. **Evaluating the Options**:
- **In Threidia**: This structure is not found in Gymnosperms.
- **Archegonia**: Present in Gymnosperms.
- **Antheridia**: Present in Gymnosperms.
- **None of these**: This option implies that all listed structures are found in Gymnosperms, which is incorrect.

4. **Conclusion**:
- The correct answer is **In Threidia**, as it is not a structure associated with Gymnosperms.

### Final Answer:
**In Threidia** is not found in Gymnosperms.

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