An element which helps in joining the subunits of ribosomes is

Options

A. Ethylene
B. Coenzyme A
C. Ferredoxin
D. Auxin

Answer

To answer the question about the element that helps in joining the subunits of ribosomes, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of Ribosomes**: Ribosomes are cellular structures that play a crucial role in protein synthesis, also known as translation. They consist of two subunits: a larger subunit and a smaller subunit.

2. **Identify the Elements Mentioned**: The question mentions several elements: ethylene, coenzyme A, ferredoxin, and auxin. We need to determine which of these is involved in the joining of ribosomal subunits.

3. **Analyze Each Element**:
- **Ethylene**: This is a plant hormone involved in processes like fruit ripening, but it does not play a role in ribosome function.
- **Coenzyme A**: This is an organic molecule that assists in various biochemical reactions, including those involving enzymes. It is important for metabolic processes but is not directly involved in ribosome subunit joining.
- **Ferredoxin**: This is a protein involved in electron transport during photosynthesis, not in ribosome assembly.
- **Auxin**: This is another plant hormone that influences growth but does not relate to ribosome function.

4. **Identify the Correct Answer**: The correct choice is **coenzyme A**. While it is not a direct component of ribosomes, it is essential for various enzymatic reactions that support cellular functions, including those related to ribosome assembly.

5. **Conclusion**: The element that helps in the joining of the subunits of ribosomes is **coenzyme A**.

### Final Answer:
The element which helps in joining the subunits of ribosomes is **coenzyme A**.