A dielectric cylinder of a radius is infinite long. Its volume charge density varies directly as the distance from the cylinder. If P is zero at the axis and Ps on the surface, the electric intensity due to it is :

A. Psa^3/ 3E0a at a point distant 'r' outside it
B. Psr^2/ 3E0a at a point distant  'r' inside it
C. Ps^a/3E0 at a point on its surface
D. Ps/3E0a^2 at a point on its surface 
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