Negative $Q$ signifies a capacitive load ($Q < 0$).

Positive $Q$ signifies an inductive load ($Q > 0$).

In capacitive loads, current leads voltage, thus voltage lags current.

FACTS devices like SVCs use this principle to regulate bus voltage.

Voltage support in weak grids

Power factor improvement

Potential for overvoltage if overcompensated

Higher harmonic injection

Static Var Compensators (SVC)

Transmission line shunt compensation

In power system conventions, the generator is the source of Q; consuming negative Q is equivalent to generating positive Q.

Option B (leads) is incorrect because that describes the current behavior relative to voltage in a capacitive circuit, not the voltage itself.