Elements most readily moblised are:

Options

A. Ca,B,Fe
B. K,P,Ca
C. N,P,K
D. Cl,Fe,B

Answer

To answer the question regarding which elements are most readily mobilized in plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Mobilization in Plants**:
- Mobilization refers to the ability of certain nutrients to move from older parts of the plant (like older leaves) to newer parts (like young leaves and growing tissues).

2. **Identifying Key Nutrients**:
- Commonly discussed mobile nutrients in plants include nitrogen (N), phosphorus (P), and sulfur (S). These nutrients can be transported through the plant's vascular system.

3. **Examining the Role of Nitrogen**:
- Nitrogen is primarily transported in the form of amino acids and is essential for various plant functions, including growth and development.

4. **Considering Phosphorus and Sulfur**:
- Phosphorus is also mobile and can be transferred from older tissues to younger ones. Sulfur, while less abundant, can similarly be mobilized.

5. **Excluding Non-Mobile Elements**:
- Elements like calcium (Ca) are generally considered immobile in plants. They do not move from older tissues to younger ones, so any options including calcium can be eliminated.

6. **Conclusion**:
- Based on the analysis, the elements that are most readily mobilized in plants are nitrogen and phosphorus. Therefore, the correct answer to the question is that nitrogen and phosphorus are the elements most readily mobilized.

### Final Answer:
The elements most readily mobilized are nitrogen and phosphorus.

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