The correct option is C admittance
To be consistent, we need a complementary measure representing the reciprocal of impedance. The name for this measure is admittance. Admittance is measured in the unit of Siemens, and its symbol is “Y”. Like impedance, admittance is a complex quantity rather than a scalar. Again, we see a certain logic to the naming of this new term: while impedance is a measure of how much alternating current is impeded in a circuit, admittance is a measure of how much current is admitted.