The correct answer is: C. A purely capacitive circuit’s ability to pass current.
Capacitive susceptance is a measure of how easily current can flow through a capacitor. It is denoted by the symbol $B_C$ and has units of siemens (S). The reciprocal of capacitive susceptance is capacitive reactance, which is denoted by the symbol $X_C$ and has units of ohms (Ω).
Capacitive susceptance is given by the following equation:
$$B_C = \frac{1}{X_C} = \frac{1}{2\pi fC}$$
where $f$ is the frequency of the AC signal in hertz (Hz) and $C$ is the capacitance in farads (F).
Capacitive susceptance is positive, which means that it allows current to flow through a capacitor. The amount of current that flows through a capacitor is proportional to the capacitive susceptance.
A purely capacitive circuit is a circuit that contains only capacitors. In a purely capacitive circuit, the current leads the voltage by 90 degrees. This is because the capacitor stores charge when the voltage is increasing, and then releases that charge when the voltage is decreasing.
The ability of a purely capacitive circuit to pass current is determined by its capacitive susceptance. The higher the capacitive susceptance, the more easily current can flow through the circuit.