Assertion (A): Bending of a conducting wire effects electrical resistance.
Reason( R): Resistance of a wire depends on resistivity of that material.

Options

A. both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is not the correct explanation of A.
C. A is true but R is false
D. A is false but R is true

Answer

To solve the question, we need to analyze the two statements: Assertion (A) and Reason (R).

### Step 1: Analyze the Assertion (A)
The assertion states: "Bending of a conducting wire affects electrical resistance."

- When a conducting wire is bent, its physical structure changes. Although the material remains the same, the bending can cause slight changes in the crystalline structure at the points of bending. This structural change can lead to variations in the electrical resistance of the wire. Therefore, the assertion is **correct**.

### Step 2: Analyze the Reason (R)
The reason states: "Resistance of a wire depends on the resistivity of that material."

- Resistance (R) is indeed given by the formula \( R = \rho \frac{L}{A} \), where \( \rho \) is the resistivity of the material, \( L \) is the length of the wire, and \( A \) is the cross-sectional area. This means that the resistance does depend on the resistivity of the material. Therefore, the reason is also **correct**.

### Step 3: Determine the Relationship Between A and R
Now we need to determine if the reason correctly explains the assertion.

- While the reason correctly states that resistance depends on resistivity, it does not explain why bending the wire affects resistance. The change in resistance due to bending is more related to the change in the structure of the wire rather than the resistivity of the material itself. Thus, while both statements are true, the reason does not adequately explain the assertion.

### Conclusion
Both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion. Therefore, the answer is:

**Assertion (A) is true, Reason (R) is true, but R is not the correct explanation of A.**

### Final Answer
The correct option is: **Option 2: A and R are true, but R is not the correct explanation of A.**

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