Which is the criterion, on the basis of which, you will determine that particular element I essential ?

Options

A. In its absence, plant is unable to complete its life cycle
B. Element is specific
C. It has direct role in metabolism
D. All of the above

Answer

To determine whether a particular element is essential for plants, we can use three key criteria. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understanding Essential Elements**:
- An essential element is one that a plant requires for its growth and development.

2. **First Criterion**:
- A plant cannot complete its life cycle without the element.
- This means that if the element is absent, the plant will not be able to grow, reproduce, or carry out its life functions.

3. **Second Criterion**:
- No other element can perform the same function as the essential element.
- This indicates that the role of the element is unique and cannot be substituted by any other element.

4. **Third Criterion**:
- The element is directly involved in plant nutrition.
- This means that the element plays a crucial role in metabolic processes and is necessary for the plant's physiological functions.

5. **Evaluating the Options**:
- The question provides four options to choose from regarding the criteria for determining if an element is essential.
- Option A states that in its absence, the plant is unable to complete its life cycle (this aligns with the first criterion).
- Option B states that the element is specific (this aligns with the second criterion).
- Option C states that it has a direct role in plant nutrition (this aligns with the third criterion).
- Option D states "all of the above," which encompasses all the criteria mentioned.

6. **Conclusion**:
- Since all the options A, B, and C are correct and represent the criteria for determining if an element is essential, the correct answer is option D: all of the above.

### Final Answer:
- The correct answer is **Option D: All of the above**.