Explanation: Class A amplifiers operate in a way that the active device conducts for the entire 360 degrees of the input signal cycle. This continuous conduction ensures that the output signal is a faithful, non-clipped reproduction of the input, resulting in the highest linearity and lowest distortion compared to other classes. They are always biased "on." In contrast, Class B amplifiers conduct for only 180 degrees, amplifying just one-half of the input waveform, which introduces "crossover distortion." Class C amplifiers conduct for significantly less than 180 degrees, making them highly nonlinear and unsuitable for linear amplification of complex signals; they are often used for RF power stages where a resonant tank circuit filters the output to restore the sine wave. Class AB amplifiers conduct for slightly more than 180 degrees, reducing crossover distortion found in Class B, but still not achieving the perfect linearity of Class A.