Assertion (A) : Lead leaves a black amrek on paore
Reason (R) : Lead is used for making lead pencils .

Options

A. If both (A) and (R) are correct and (R) is correct explanation of (A)
B. If both (A) and (R) are correct and (R) is not 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 1: Analyze the Assertion
The assertion states: "Lead leaves a black mark on paper."
- This statement is **true**. Lead, when used in a pencil, can leave a mark on paper. However, it is important to note that the material commonly used in pencils is actually graphite, not lead.

### Step 2: Analyze the Reason
The reason states: "Lead is used for making lead pencils."
- This statement is **false**. Although the term "lead pencil" is commonly used, the core material used in these pencils is graphite, which is safe and non-toxic. Lead itself is a toxic substance and is not used in the manufacturing of pencils.

### Step 3: Conclusion
- Since the assertion is true and the reason is false, we can conclude that the correct answer is that the assertion is true but the reason is not.

### Final Answer
- The correct option is **C**: Assertion is true, but Reason is false.

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