In which type of device does current lead voltage?

In a capacitive device, current leads voltage due to the nature of how capacitors operate in an AC circuit. When a capacitor is charged, it stores electrical energy in an electric field. As the alternating current flows through the circuit, the capacitor charges and discharges, resulting in the current reaching its maximum value before the voltage does. This behavior means that the phase angle of the current waveform is ahead of the voltage waveform.

In contrast, inductive devices would show the opposite behavior; in those, the voltage leads the current. Resistive devices do not cause any phase difference between current and voltage; they are in phase. Reactive components, which include both inductive and capacitive aspects, experience phase shifts but in the case of purely capacitive devices, it is specifically the current that leads the voltage. Thus, this phenomenon in capacitors is a fundamental concept in AC circuit theory, which is why the correct choice is capacitive.