(ii) Carbon reduction is used for the extraction of :

Options

A. Fe
B. K
C. Al
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Carbon Reduction**: Carbon reduction is a method used to extract metals from their ores. It involves using carbon (often in the form of coke) to reduce metal oxides to their elemental form.

2. **Identifying Reactive Metals**: Metals like potassium and aluminum are highly reactive and cannot be extracted using carbon reduction. Instead, they require more advanced methods such as electrolysis for extraction.

3. **Focusing on Less Reactive Metals**: Metals that are less reactive, such as iron, can be extracted using carbon reduction. Iron is found in nature primarily as iron oxide (Fe2O3).

4. **The Reduction Process**: In the carbon reduction process, carbon reacts with the oxygen in the metal oxide. For example, when iron(III) oxide (Fe2O3) is heated with carbon, it produces iron and carbon monoxide:
\[ \text{Fe}_2\text{O}_3 + 3\text{C} \rightarrow 2\text{Fe} + 3\text{CO} \]

5. **Conclusion**: Therefore, carbon reduction is specifically used for the extraction of iron from its oxide ores.

**Final Answer**: Carbon reduction is used for the extraction of iron.

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