How do inductors behave at low and high frequencies?

• A. At low frequencies, inductors behave as an open circuit; at high frequencies, they behave as a short circuit.
• B. At low frequencies, inductors behave as short circuits; at high frequencies, they behave as open circuits.
• C. Inductors behave as resistors with constant value regardless of frequency.
• D. Inductors store energy without affecting circuit connectivity.

Answer: (B)

Inductors have an impedance that depends on frequency. The inductive reactance is X_L = ωL, so as frequency ω goes to zero, X_L goes to zero, and the coil looks like a short circuit. As frequency increases, X_L grows larger, and the inductor resists the current more and more, acting like an open circuit at very high frequencies. In DC (zero frequency) it behaves like a short; for high-frequency AC signals it presents large impedance and limits current flow.

That’s why the correct view is that inductors act as short circuits at low frequencies and as open circuits at high frequencies. The other statements don’t match this frequency-dependent behavior (constant resistance, or opposite roles, or focusing only on energy storage without connectivity).