Explanation: Class C amplifiers are designed for maximum efficiency in RF power amplification, not for fidelity in reproducing broadband signals like audio. In Class C operation, the plate current flows for significantly less than 180 degrees of the input cycle (as little as 120 degrees). This extreme non-linearity means that, inherently, only a small portion of the input waveform is amplified. This leads to two key issues for audio: 1. **Distortion (Option A):** Even in a push-pull Class C configuration, where two tubes alternate, the combined conduction period still leaves significant gaps in the waveform. This results in severe distortion, rendering the output unacceptable for audio reproduction, which requires faithful amplification of the entire signal. 2. **Tank Circuit Limitation (Option B):** Class C amplifiers typically rely on a resonant tank circuit in the output stage to reconstruct the complete waveform. The "flywheel effect" of the tank circuit fills in the missing portions of the current pulses, producing a clean sinusoidal output. However, a tank circuit is highly frequency-selective, designed to resonate at a single frequency or a very narrow band. Audio signals, by definition, are composed of a wide range of frequencies. A tank circuit cannot simultaneously reproduce this broad spectrum of audio frequencies; it would effectively filter out everything but its resonant frequency, causing massive distortion.