Assertion (A): The polar of centre of circle w.r.t same circle does not exist.
Reason (R), Distance between parallel tangents of circle is diameter of circle.
The correct answer is

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true and 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 assertion (A) and the reason (R) provided:

**Assertion (A):** The polar of the center of a circle with respect to the same circle does not exist.

**Reason (R):** The distance between parallel tangents of a circle is the diameter of the circle.

### Step-by-Step Solution:

1. **Understanding the Assertion (A):**
- The polar of a point with respect to a circle is defined in terms of tangents drawn from that point to the circle.
- For the center of the circle, if we try to draw tangents, we find that we cannot draw two tangents of equal length from the center to the circle since the tangents from the center would be at the same point on the circle (the radius). Therefore, the polar of the center does not exist.

2. **Understanding the Reason (R):**
- The distance between two parallel tangents to a circle can be calculated. If we have a circle of radius \( r \), the distance between the two parallel tangents is indeed equal to the diameter of the circle, which is \( 2r \).
- This statement is true.

3. **Evaluating the Relationship Between A and R:**
- While both statements A and R are true, the reason (R) does not explain why the assertion (A) is true. The assertion is about the polar of the center, while the reason discusses the distance between parallel tangents, which is a separate concept.

4. **Conclusion:**
- Therefore, the correct answer is that both A and R are true, but R is not the correct explanation of A.

### Final Answer:
Both A and R are true, but R is not the correct explanation of A.

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