Assertion: Durig calcination the ore is heated well below its melting point in the limited supply of air or absence of air.
Reason: The process of calcination is carried out for sulphide ores.

Options

A. If both (A) and ( R) are correct and ( R) is the correct explanation of (A).
B. If both (A) and ( R) are correct, but ( R) is not the correct explanation of (A).
C. If (A) is correct, but ( R) is incorrect.
D. If (A) is incorrect, but ( R) is correct.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that during calcination, the ore is heated well below its melting point in limited supply of air or absence of air.
- This is true. Calcination is a thermal treatment process where ores are heated to a temperature below their melting point in a controlled atmosphere, often to remove volatile impurities or to induce thermal decomposition.

2. **Understanding the Reason**:
- The reason given is that the process of calcination is carried out for sulphide ores.
- This statement is incorrect. Calcination is primarily used for carbonate ores, such as calcium carbonate, which decomposes to form calcium oxide and carbon dioxide. For sulphide ores, the process typically used is roasting, which involves heating in the presence of air to convert sulphides into oxides.

3. **Conclusion**:
- Since the assertion is correct and the reason is incorrect, we conclude that the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
- The correct option is **C**: Assertion is correct, Reason is wrong.