Elater mechanism for seed dispersal is exhibited by

Options

A. Riccia
B. Dryopteris
C. Funaria
D. Marchantia.

Explanation

To solve the question regarding which organism exhibits the elater mechanism for seed dispersal, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Elater Mechanism**:
- Elaters are specialized structures that aid in the dispersal of spores. They are typically hygroscopic, meaning they can absorb moisture and change shape in response to humidity, which helps in the dispersal process.

2. **Identify the Organisms in the Options**:
- The options given are Rickettsia, Dryopteris, Finaria, and Markentia. We need to analyze each of these to see if they possess elaters.

3. **Analyze Each Option**:
- **Rickettsia**: This is a genus of bacteria and does not have any structures related to seed or spore dispersal.
- **Dryopteris**: This is a genus of ferns (pteridophytes) and does not possess elaters.
- **Finaria**: This is a genus of mosses. While mosses have a different mechanism for spore dispersal, they do not have elaters.
- **Markentia**: This is a genus of liverworts (bryophytes) that does exhibit the elater mechanism for spore dispersal. The elaters are long, spindle-shaped structures with spiral thickenings that help in the dispersal of spores from the capsule.

4. **Conclusion**:
- Based on the analysis, the correct answer is **Markentia**, as it is the only option that exhibits the elater mechanism for spore dispersal.

### Final Answer:
The elater mechanism for seed dispersal is exhibited by **Markentia**.

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