Final answer:
Characteristic impedance refers to the impedance of a cable, which is an AC analog to resistance in a DC circuit, considering the effects of resistance, inductance, and capacitance.
Step-by-step explanation:
Characteristic impedance refers to the quality of a cable that describes its inherent resistance to alternating current (AC) and is symbolized by the letter 'Z'. It is a measure of the combined effect of resistance (R), inductive reactance (XL), and capacitive reactance (XC). The characteristic impedance of a cable does not refer to resistance alone. Instead, it refers to the impedance of the cable, which is the AC analog to resistance in a direct current (DC) circuit. Impedance takes into account the resistance as well as the effects of inductance and capacitance. The formula Z = R² + (XL-XC)² is used to calculate it. Therefore, the correct answer to what the quality of a cable characteristic impedance refer to is (d) Impedance.