Hydroponics is growing plants in

Options

A. Solution of mineral nutrients
B. Phytotron
C. Liquid culture medium
D. Solid culture medium

Answer

**Step-by-Step Solution:**

1. **Understanding Hydroponics**: Hydroponics is a method of growing plants without soil. Instead, it utilizes a nutrient-rich water solution to provide the essential minerals that plants need for growth.

2. **Identifying the Correct Option**: The question asks where hydroponics is used for growing plants. The options include:
- A) Solution of mineral nutrients
- B) Hydrotron
- C) Liquid culture medium
- D) Solid culture medium

3. **Analyzing the Options**:
- **Option A**: Solution of mineral nutrients - This is the primary method used in hydroponics, as it provides the necessary nutrients directly to the plant roots.
- **Option B**: Hydrotron - This is not a standard term associated with hydroponics.
- **Option C**: Liquid culture medium - While hydroponics can involve liquid mediums, this term is broader and not specific to hydroponics.
- **Option D**: Solid culture medium - This is not used in hydroponics, as the method specifically avoids soil.

4. **Conclusion**: Based on the analysis, the correct answer is **A) Solution of mineral nutrients**. This method was notably demonstrated by Julius von Sachs in 1816, who showed that plants could thrive in a nutrient solution without soil.

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