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 determine which element is a constituent of thiamine, biotin, Coenzyme A, and ferredoxin, we can follow these steps:

### Step 1: Identify the compounds
- Thiamine (Vitamin B1), biotin (Vitamin B7), Coenzyme A, and ferredoxin are all important biological molecules involved in various metabolic processes.

### Step 2: Analyze the options
- The options provided are iron, sulphur, magnesium, and copper. We need to evaluate which of these elements is a constituent of the mentioned compounds.

### Step 3: Research the composition of each compound
- **Thiamine**: Contains sulfur in its structure.
- **Biotin**: Also contains sulfur in its structure.
- **Coenzyme A**: Contains sulfur as part of its structure.
- **Ferredoxin**: Contains iron and sulfur in its structure, but sulfur is a key component.

### Step 4: Determine the common element
- From the analysis, we can see that sulfur is a common constituent in thiamine, biotin, and Coenzyme A. While ferredoxin contains iron, it also contains sulfur, making sulfur the common element among the majority.

### Step 5: Conclude the answer
- Therefore, the element that is a constituent of thiamine, biotin, Coenzyme A, and ferredoxin is **sulfur**.

### Final Answer
- The correct answer is **sulfur** (Option 2).

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