By which layer the metal is covered galvinization?

Options

A. Gallium
B. Copper
C. Zinc
D. Tin

Explanation

**Step-by-Step Solution:**

1. **Understanding Galvanization:**
- Galvanization is a process used to protect metals from corrosion, particularly iron and steel. It involves coating the metal with another metal that is more reactive.

2. **Identifying the Inner Metal:**
- In most cases, the inner metal that is being protected is iron (Fe). Iron is prone to rusting when exposed to moisture and air.

3. **Choosing the Coating Metal:**
- To prevent corrosion, a coating of a more reactive metal is applied to the surface of iron. This is crucial because the more reactive metal will corrode first, thus protecting the iron underneath.

4. **Referencing the Reactivity Series:**
- The reactivity series is a list of metals arranged in order of decreasing reactivity. In this series, zinc (Zn) is more reactive than iron (Fe) but less reactive than alkali metals like potassium and sodium.

5. **Selecting the Correct Metal for Galvanization:**
- Among the common metals, zinc is typically used for galvanization because it is more reactive than iron. This means that when zinc is used as a coating, it will corrode before the iron does, thus providing protection.

6. **Conclusion:**
- Therefore, the metal used to cover iron in the galvanization process is zinc.

**Final Answer:**
The metal used to cover iron in galvanization is **zinc**.

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