Hydroponics requires

Options

A. purified water
B. impure water
C. mineral nutrient salt
D. both (1) and (3)

Answer

### Step-by-Step Text Solution:

1. **Understanding Hydroponics**: Hydroponics is a method of growing plants without soil, using a nutrient solution instead. This technique allows for the direct delivery of essential nutrients to the plants.

2. **Essential Requirements**: For hydroponics, the primary requirement is a nutrient solution that contains all the essential mineral nutrients necessary for plant growth. This solution replaces the need for soil.

3. **Water Quality**: The water used in hydroponics must be purified. Impure water can introduce contaminants that may harm the plants or affect their growth negatively.

4. **Nutrient Solution Composition**: The nutrient solution must include various mineral nutrients and salts that are vital for the plants' development. This includes elements like nitrogen, phosphorus, potassium, calcium, magnesium, and trace elements.

5. **Conclusion**: Therefore, hydroponics requires purified water and mineral nutrient salts. The correct answer to the question is that hydroponics requires both purified water and mineral nutrient salts.