Which of the following is combined with an inductor to make a resonant circuit?

A resonant circuit, also known as a tuned circuit, is created by combining an inductor and a capacitor. These two components work together by passing stored energy back and forth. The inductor stores energy in a magnetic field, while the capacitor stores energy in an electric field. When connected together, this energy exchange naturally oscillates at a specific frequency, known as the resonant frequency. This principle is exactly how radios tune into specific frequencies while rejecting others. Other components like resistors, potentiometers (variable resistors), or Zener diodes do not have this dual energy-storage relationship. They cannot create the oscillating resonance required for tuning radio signals.