The double fertilization is the only characteristic of :-

Options

A. Bryophytes
B. Pteridophytes
C. Gymnosperm
D. Angiosperm

Answer

### Step-by-Step Solution:

1. **Understanding Double Fertilization**:
- Double fertilization is a unique process in which two sperm cells fertilize two different structures within the ovule. One sperm fertilizes the egg cell, forming the zygote, while the other sperm fuses with two polar nuclei to form the triploid endosperm.

2. **Identifying the Groups**:
- The question provides four options: Dryophytes, Pteridophytes, Gymnosperms, and Angiosperms. We need to determine which of these groups exhibits double fertilization.

3. **Analyzing Each Option**:
- **Option A: Dryophytes**: This term generally refers to plants that grow in dry environments, but it is not a specific classification in plant taxonomy and does not relate to double fertilization.
- **Option B: Pteridophytes**: This group includes ferns and their relatives. They reproduce via spores and do not exhibit double fertilization.
- **Option C: Gymnosperms**: These are seed-producing plants like conifers. They undergo fertilization, but not double fertilization.
- **Option D: Angiosperms**: This group includes flowering plants, which are characterized by the process of double fertilization.

4. **Conclusion**:
- Based on the analysis, the correct answer is **Option D: Angiosperms**, as double fertilization is a defining characteristic of this group.

### Final Answer:
The double fertilization is the only characteristic of **Angiosperms**.

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