The unique feature of Bryophytes compared to other green plant groups is that :-

Options

A. They produce spores
B. They lack vascular tissue
C. They lack root
D. Their sporophyte is attached to gametophyte

Answer

### Step-by-Step Solution:

1. **Understanding Bryophytes**: Bryophytes are non-vascular plants that include mosses, liverworts, and hornworts. They are unique among plant groups due to their specific reproductive and structural characteristics.

2. **Key Features of Bryophytes**:
- Bryophytes produce spores, which is a common feature shared with other plant groups, so this option is not unique.
- They lack vascular tissues (xylem and phloem), which distinguishes them from higher plants. However, this is also a characteristic of other non-vascular plants.
- Bryophytes do not have true roots; instead, they have structures called rhizoids that help anchor them to the substrate. This feature is also found in some other non-vascular plants.
- The most unique feature of bryophytes is that their sporophyte is attached to the gametophyte. The sporophyte is dependent on the gametophyte for nutrition and remains attached throughout its life cycle.

3. **Conclusion**: Based on the above analysis, the unique feature of bryophytes compared to other green plant groups is that their sporophyte remains attached to the gametophyte.

### Final Answer:
The unique feature of Bryophytes compared to other green plant groups is that **their sporophyte is attached to the gametophyte**.

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