Biofertilisers are the living organisms which

Options

A. bring about soil nutrient enrichment
B. maximise the ecological benefits
C. minimise the environmental hazards
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding Biofertilizers**: Biofertilizers are defined as living organisms, particularly microorganisms, that enhance the nutrient content and fertility of the soil. They play a crucial role in sustainable agriculture.

2. **Characteristics of Biofertilizers**:
- **Increase Soil Fertility**: Biofertilizers contribute to the enrichment of soil nutrients, making them more fertile.
- **Nutrient Content Enhancement**: They help in increasing the nutrient content in the soil, which is essential for plant growth.
- **Environmental Safety**: Biofertilizers do not cause environmental damage, making them a safer alternative to chemical fertilizers.

3. **Examples of Biofertilizers**:
- **Nitrogen-Fixing Bacteria**: Certain bacteria, such as Rhizobium, can fix atmospheric nitrogen, converting it into a form that plants can use.
- **Cyanobacteria**: These are also known as blue-green algae, which can fix nitrogen and contribute to soil fertility.
- **Mycorrhizae**: This is a symbiotic relationship between fungi and plant roots that enhances nutrient and water uptake from the soil.

4. **Analyzing the Options**:
- **Option A**: "Bring about soil nutrient enrichment" - This is true as biofertilizers enhance nutrient availability.
- **Option B**: "Maximize the ecological benefits" - This is also true as they promote a healthy ecosystem.
- **Option C**: "Minimize the environmental hazards" - This is correct since biofertilizers are environmentally friendly.
- **Option D**: "All of these" - Since all the previous statements are true, this option is correct.

5. **Conclusion**: The correct answer is **D: all of these**. Biofertilizers indeed bring about soil nutrient enrichment, maximize ecological benefits, and minimize environmental hazards.

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