Go through the following matches
(i) Calcium - Required by meristematic and differentiating tissues
(ii) Nitrogen - Mineral element required by plants in the greatest amount.
(iii) Magnesium - Activates enzymes involved in DNA and RNA synthesis.
(iv) Iron - Mainly obtained by plants in ferrous form
Which of these are correct

Options

A. (i), (ii) and (iii)
B. (ii) and (iii)
C. (i), (iii) & (iv)
D. All are correct

Answer

To solve the question regarding the matches of mineral elements required by plants, we will evaluate each statement one by one:

### Step-by-Step Solution:

1. **Evaluate Calcium**:
- **Statement**: Calcium - Required by meristematic and differentiating tissues.
- **Analysis**: This statement is correct. Calcium is essential for the structural integrity of cell walls and is crucial for the functioning of meristematic tissues, which are responsible for growth and differentiation in plants.

2. **Evaluate Nitrogen**:
- **Statement**: Nitrogen - Mineral element required by plants in the greatest amount.
- **Analysis**: This statement is also correct. Nitrogen is a vital nutrient for plants, as it is a key component of amino acids, proteins, and nucleic acids. It is indeed required in larger quantities compared to other minerals.

3. **Evaluate Magnesium**:
- **Statement**: Magnesium - Activates enzymes involved in DNA and RNA synthesis.
- **Analysis**: This statement is correct as well. Magnesium acts as a cofactor for several enzymes, including those involved in DNA and RNA synthesis, such as DNA polymerase and RNA polymerase.

4. **Evaluate Iron**:
- **Statement**: Iron - Mainly obtained by plants in ferrous form.
- **Analysis**: This statement is incorrect. While plants can absorb iron in both ferrous (Fe²⁺) and ferric (Fe³⁺) forms, the primary form in which iron is absorbed by plants is actually the ferric form (Fe³⁺). Therefore, stating that iron is mainly obtained in ferrous form is misleading.

### Conclusion:
- The correct matches are:
- (i) Calcium - Correct
- (ii) Nitrogen - Correct
- (iii) Magnesium - Correct
- (iv) Iron - Incorrect

Thus, the answer is that three out of the four statements are correct.