Which of the following is a biofertilizer?

Options

A. Funaria
B. Fern
C. Anabaena
D. Fungus

Answer

To determine which of the following options is a biofertilizer, we need to analyze each option provided: Funaria, Fern, Anabena, and Fungus.

### Step-by-Step Solution:

1. **Understanding Biofertilizers**:
- Biofertilizers are natural fertilizers that consist of living microorganisms. They enhance soil fertility and crop yield without the use of harmful chemicals.

2. **Evaluating Funaria**:
- Funaria is a type of moss. While it is autotrophic, it does not contribute to soil fertility or act as a fertilizer. In fact, its growth can lead to stagnant water conditions that may harm crops.
- **Conclusion**: Funaria is not a biofertilizer.

3. **Evaluating Fern**:
- Ferns are vascular plants but do not play a significant role in enhancing soil fertility or nitrogen fixation. They are not used as biofertilizers.
- **Conclusion**: Fern is not a biofertilizer.

4. **Evaluating Anabena**:
- Anabena is a blue-green algae (cyanobacteria) known for its ability to fix nitrogen. It forms a symbiotic relationship with leguminous plants, enhancing soil fertility and crop yield.
- **Conclusion**: Anabena is a biofertilizer.

5. **Evaluating Fungus**:
- While some fungi can act as biofertilizers, not all fungi have this capability. Therefore, without a specific type of fungus mentioned, we cannot classify "fungus" as a biofertilizer.
- **Conclusion**: Fungus is not a definitive answer as a biofertilizer.

### Final Answer:
The most appropriate answer is **Anabena**, as it is a recognized biofertilizer due to its nitrogen-fixing capabilities.

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