Hydroponics is a technique of growing:

Options

A. submerged plants
B. free-floating aquatic plants
C. terrestrial plants in sand
D. plants in aqueous balanced nutrient medium

Answer

**Step-by-Step Solution:**

1. **Understanding Hydroponics**: Hydroponics is a method of growing plants without soil, using a nutrient-rich water solution instead. This technique allows plants to absorb nutrients directly from the water.

2. **Analyzing the Options**: The question presents four options regarding what hydroponics involves:
- Submerged plants
- Free-floating aquatic plants
- Terrestrial plants in sand
- Plants in aqueous balanced nutrient medium

3. **Evaluating Each Option**:
- **Submerged plants**: These are plants that grow completely underwater, which does not align with hydroponics.
- **Free-floating aquatic plants**: While these plants float on water, they do not necessarily use a nutrient solution like hydroponics.
- **Terrestrial plants in sand**: This option implies the use of soil (sand), which contradicts the concept of hydroponics.
- **Plants in aqueous balanced nutrient medium**: This option accurately describes hydroponics, as it involves growing plants in a water-based nutrient solution.

4. **Conclusion**: After evaluating all options, the correct answer is that hydroponics is a technique of growing "plants in aqueous balanced nutrient medium."

**Final Answer**: Hydroponics is a technique of growing plants in aqueous balanced nutrient medium.

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