Which one of the following vitamin contains a metal atom ?

Options

A. Vitamin `A`
B. Vitamin `B_(2)`
C. Vitamin `B_(6)`
D. Vitamin `B_(12)`

Answer

To determine which vitamin contains a metal atom, we can follow these steps:

### Step 1: Identify the Vitamins
First, we need to identify the vitamins mentioned in the question. The common vitamins that are often discussed include:
- Vitamin A
- Vitamin B2 (Riboflavin)
- Vitamin B6 (Pyridoxine)
- Vitamin B12 (Cyanocobalamin)

### Step 2: Research Each Vitamin
Next, we will look into each vitamin to see if they contain any metal atoms.

- **Vitamin A**: This vitamin is primarily composed of organic compounds and does not contain any metal.
- **Vitamin B2 (Riboflavin)**: This vitamin is also an organic compound and does not contain any metal.
- **Vitamin B6 (Pyridoxine)**: Like the previous vitamins, it is an organic compound without any metal.
- **Vitamin B12 (Cyanocobalamin)**: This vitamin is unique among the listed vitamins because it contains cobalt, which is a metal atom.

### Step 3: Conclusion
Based on the analysis, we conclude that the vitamin that contains a metal atom is **Vitamin B12** (Cyanocobalamin) due to the presence of cobalt.

### Final Answer
The vitamin that contains a metal atom is **Vitamin B12**.

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