Assertion: `CuFeS_(2)` is concentrated by froath floatation method
Reason : `CuFeS_(2)` is main ore of copper.

Options

A. If both assetion and reason are CORRECT, and reason is the CORRECT explanation of the assertion
B. If both assertion and reason are CORRECT, but reason is NOT the CORRECT explanation of the assertion
C. If assertion is CORRECT but reason is INCORRECT
D. If assertion is INCORRECT but reason is CORRECT

Answer

To solve the question regarding the assertion and reason provided, we will analyze each part step by step.

### Step 1: Understand the Assertion
The assertion states that `CuFeS2` (copper pyrite) is concentrated by the froth flotation method.

**Explanation:**
- The froth flotation method is a process used for the concentration of sulfide ores.
- `CuFeS2` is indeed a sulfide ore, specifically the main ore of copper.

### Step 2: Validate the Assertion
Since `CuFeS2` is a sulfide ore and the froth flotation method is specifically designed for the concentration of sulfide ores, the assertion is **correct**.

### Step 3: Understand the Reason
The reason states that `CuFeS2` is the main ore of copper.

**Explanation:**
- `CuFeS2` is widely recognized as the primary source of copper, containing a significant amount of copper in its composition.

### Step 4: Validate the Reason
The reason is also **correct** because `CuFeS2` is indeed the main ore of copper.

### Step 5: Analyze the Relationship Between Assertion and Reason
Now, we need to determine if the reason is the correct explanation of the assertion.

- While both the assertion and reason are correct, the reason does not explain why `CuFeS2` is concentrated by the froth flotation method. The froth flotation method is used for sulfide ores in general, not specifically because `CuFeS2` is the main ore of copper.

### Conclusion
Both the assertion and reason are correct, but the reason is not the correct explanation of the assertion. Therefore, the correct answer is that both the assertion and reason are correct, but the reason is not the correct explanation of the assertion.

### Final Answer
Both assertion and reason are correct, but reason is not the correct explanation of assertion.

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