Which of the following pair is correct ?

Options

A. Mn - formation of chlorophyll
B. P - required in meristematic tissues
C. Ca - formation of the mitotic spindle
D. Cu - synthesis of auxin

Answer

To solve the question, we need to evaluate each of the pairs provided and determine which one is correct based on our knowledge of plant nutrients and their functions.

### Step-by-Step Solution:

1. **Evaluate the first pair: Formation of chlorophyll with manganese.**
- Chlorophyll formation primarily requires magnesium, not manganese. Manganese is involved in the splitting of water during photosynthesis but is not a component of chlorophyll.
- **Conclusion:** This pair is incorrect.

2. **Evaluate the second pair: Formation of chlorophyll with phosphorous, required in meristematic tissue.**
- Phosphorus is essential for nucleic acids and energy transfer (ATP) but is not specifically required in large quantities in meristematic tissues. Instead, potassium is more critical in these tissues.
- **Conclusion:** This pair is incorrect.

3. **Evaluate the third pair: Formation of the mitotic spindle with calcium.**
- Calcium is indeed important for cell division and plays a crucial role in the formation of the mitotic spindle. It is a macronutrient that is required in larger quantities.
- **Conclusion:** This pair is correct.

4. **Evaluate the fourth pair: Synthesis of auxin with copper.**
- Auxin, a plant hormone involved in growth regulation, is primarily synthesized with the help of tryptophan and requires zinc rather than copper.
- **Conclusion:** This pair is incorrect.

### Final Answer:
The correct pair is: **Formation of the mitotic spindle with calcium.**

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