Which of the following mainly react in extraction of chromium and manganeses?

Options

A. Al
B. Zn
C. Cu
D. Mg

Explanation

To answer the question regarding which metal mainly reacts in the extraction of chromium and manganese, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Extraction Process**: The extraction of chromium and manganese typically involves a metallurgical process. In this case, we are looking for the specific method used for their extraction.

2. **Identify the Method**: The method commonly used for the extraction of chromium and manganese is the Aluminium Thermite process. This process involves the use of aluminium as a reducing agent.

3. **Role of Aluminium**: In the Aluminium Thermite process, aluminium reacts with the oxides of chromium and manganese. The aluminium reduces these metal oxides to their respective metals.

4. **Chemical Reaction**: The general reaction can be represented as:
\[ \text{Cr}_2\text{O}_3 + 2\text{Al} \rightarrow 2\text{Cr} + \text{Al}_2\text{O}_3 \]
\[ \text{MnO}_2 + 2\text{Al} \rightarrow \text{Mn} + \text{Al}_2\text{O}_3 \]
Here, chromium oxide and manganese oxide are reduced to chromium and manganese respectively.

5. **Conclusion**: From the above analysis, we conclude that the metal that mainly reacts in the extraction of chromium and manganese is Aluminium.

### Final Answer:
The correct answer is **Aluminium**.

---