Which of the following is the unique feature of brophytes ?

Options

A. Presence of vascular bundles
B. Reproduction only by the formation of gametes
C. Gametophyte attached to the sporophyte
D. Sporophyte attached to the gametophyte

Answer

To solve the question regarding the unique feature of bryophytes, we will analyze each option provided and determine which one accurately describes a characteristic that is unique to bryophytes.

### Step-by-Step Solution:

1. **Understanding Bryophytes**:
- Bryophytes are non-vascular plants, meaning they do not have xylem and phloem, which are essential for the transport of water and nutrients in vascular plants.
- They are also known as thalloid plants because they lack well-defined stems, leaves, and roots.

**Hint**: Remember that bryophytes are non-vascular and often have a thallus-like structure.

2. **Analyzing the Options**:
- **Option A: Presence of vascular bundles**: This is incorrect because bryophytes do not have vascular bundles; they are non-vascular.
- **Option B: Reproduction only by the formation of gametes**: While bryophytes do reproduce via gametes, this is not unique to them as many other plant groups also reproduce this way.
- **Option C: Gametophyte attached to the sporophyte**: This is partially true, but it does not highlight the unique feature of bryophytes.
- **Option D: Sporophyte attached to the gametophyte**: This is the correct answer. In bryophytes, the sporophyte is dependent on the gametophyte for nutrition and is attached to it.

**Hint**: Focus on the relationship between gametophyte and sporophyte in bryophytes to find the unique feature.

3. **Conclusion**:
- The unique feature of bryophytes is that the sporophyte is attached to the gametophyte. This dependency is a defining characteristic of bryophytes, distinguishing them from other plant groups.

**Final Answer**: **Option D: Sporophyte attached to the gametophyte**.