Fertilizers are usually enriched in NPK which denotes

Options

A. iron, manganese and zinc
B. nitrogen, phosphorus and zinc
C. calcium and boron
D. nitrogen, phosphorus and potassium

Answer

**Step-by-Step Solution:**

1. **Understanding NPK**: The question asks what NPK stands for in the context of fertilizers. NPK is a common abbreviation used in agriculture.

2. **Identifying the Components**:
- N stands for Nitrogen.
- P stands for Phosphorus.
- K stands for Potassium.

3. **Role of Each Component**:
- **Nitrogen (N)**: It is essential for the growth of leaves and overall vegetative growth in plants.
- **Phosphorus (P)**: This nutrient is crucial for root development and is also important for the development of flowers and fruits.
- **Potassium (K)**: Potassium plays a vital role in the overall functioning of the plant, helping in various physiological processes.

4. **Choosing the Correct Option**: Based on the definitions and roles of each nutrient, we can conclude that NPK denotes Nitrogen, Phosphorus, and Potassium. Therefore, the correct answer is option D.

**Final Answer**: NPK denotes Nitrogen, Phosphorus, and Potassium (Option D).

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