Tick the correct answer in the following : Area of a sector of angle p (in degrees) of a circle with radius R is (A) \( \frac{p}{180} \times 2 \pi R \) (B) \( \frac{p}{180} \times \pi R^2 \) (C) \( \frac{p}{360} \times 2 \pi R \) (D) \( \frac{p}{720} \times 2 \pi R^2 \)