`Mg^(++)` ions play an important role in

Options

A. Association of ribosomal sub units
B. formation of primary cell wall
C. formation of secondary cell wall
D. production golgi complex

Answer

### Step-by-Step Solution:

1. **Understanding the Role of Magnesium Ions**: Magnesium ions (Mg²⁺) are essential micronutrients for plants and play various roles in biological processes.

2. **Identifying Functions of Magnesium**:
- Magnesium is crucial for the activation of enzymes involved in respiration and photosynthesis.
- It is also necessary for the synthesis of DNA and RNA.

3. **Magnesium and Chlorophyll**:
- Magnesium is a key component of chlorophyll, the pigment responsible for photosynthesis in plants. This highlights its importance in energy production.

4. **Role in Ribosomal Structure**:
- Magnesium ions help maintain the structure of ribosomes, which are essential for protein synthesis. Ribosomes consist of two subunits (large and small) in both prokaryotes and eukaryotes.

5. **Conclusion**:
- Among the options provided, the role of magnesium ions in the association of ribosomal subunits is highlighted as a significant function. Therefore, the correct answer is that Mg²⁺ ions play an important role in the association of ribosomal subunits.

### Final Answer:
Mg²⁺ ions play an important role in the association of ribosomal subunits.

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