Explanation: The **flywheel effect** accurately describes the tendency of an LC (tank) circuit to sustain oscillations due to the continuous exchange of energy between the inductor's magnetic field and the capacitor's electric field. Once excited, the stored energy keeps the current flowing and voltage changing, much like a mechanical flywheel's inertia keeps it spinning after the initial push. This property provides frequency stability and selectivity in resonant circuits, allowing them to "ring" at their resonant frequency. **Push-pull effect (A)** refers to a type of amplifier configuration, not a tank circuit characteristic. **Polarizing effect (C)** relates to material properties under an electric field or biasing, not sustained oscillation. **Parasitic oscillation (D)** describes *unwanted* oscillations in circuits, contrasting with the inherent, often desired, resonant behavior of a tank circuit.