Assertion: In the absence of an external electric Field, the dipole moment per unit volume of a polar dielectric is zero.
Reason: The dipoles of a polar dielectric are randomly oriented.
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 and R is also false.