Which of the following element is the constituent of thiamine, biotin, CoA and Ferredoxin ?

Options

A. Fe
B. S
C. Mg
D. Cu

Answer

To solve the question "Which of the following elements is the constituent of thiamine, biotin, CoA, and ferredoxin?", we can follow these steps:

### Step 1: Identify the Compounds
First, we need to identify the compounds mentioned in the question:
- Thiamine
- Biotin
- Coenzyme A (CoA)
- Ferredoxin

### Step 2: Determine the Elements Present in Each Compound
Next, we analyze each compound to find out which elements are constituents:
- **Thiamine**: Contains sulfur as part of its structure.
- **Biotin**: Also contains sulfur in its molecular structure.
- **Coenzyme A (CoA)**: Contains sulfur as it is part of the structure of CoA.
- **Ferredoxin**: This is a protein that contains iron-sulfur clusters, but sulfur is a key component.

### Step 3: Review the Options
Now, we look at the options provided:
1. Fe (Iron)
2. RN (not a standard element)
3. S (Sulfur)
4. Mg (Magnesium)
5. Cu (Copper)

### Step 4: Analyze the Options
- **Fe (Iron)**: Important for chlorophyll synthesis but not a constituent of the mentioned compounds.
- **RN**: Not applicable as it is not a recognized element.
- **S (Sulfur)**: Confirmed as a constituent of thiamine, biotin, CoA, and ferredoxin.
- **Mg (Magnesium)**: Central atom in chlorophyll, not related to the compounds listed.
- **Cu (Copper)**: Involved in enzyme activation but not a constituent of the listed compounds.

### Step 5: Conclusion
Based on the analysis, the correct answer is **S (Sulfur)**, as it is the common element found in thiamine, biotin, CoA, and ferredoxin.

### Final Answer
The correct answer is **S (Sulfur)**.

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