One among the following is the correct explanation of pedal equation of an polar curve, r=f ( ), p=r sin( ) (where p is the length of the perpendicular from the pole to the tangent & is the angle made by tangent to the curve with vector drawn to curve from pole)is _______

• A. It is expressed in terms of p & only
• B. It is expressed in terms of p & only
• C. It is expressed in terms of r & only
• D. It is expressed in terms of p& r only