Which of the following could you use to cure distorted audio caused by RF current on the shield of a microphone cable?

Using a ferrite choke is an effective solution for addressing distorted audio that results from RF current on the shield of a microphone cable. Ferrite chokes work by suppressing high-frequency noise, including RF interference, that can couple into the audio signal. They are placed around the cable and act as a high-impedance barrier to unwanted high-frequency signals.

The reason why a ferrite choke is particularly useful in this scenario is its ability to absorb and dissipate the RF energy before it can affect the microphone's signal integrity. By preventing this interference from reaching the audio equipment, you can maintain clearer audio quality and reduce distortion.

In contrast, other components like band-pass and low-pass filters are designed for different types of signal management. Band-pass filters allow a specific range of frequencies to pass while blocking others, typically used in cases where you want to isolate a particular frequency range. Low-pass filters are designed to allow low-frequency signals to pass while attenuating higher frequencies, which might not specifically target RF interference. A preamplifier increases signal strength but does not inherently eliminate RF noise, and using it without addressing the interference can actually amplify the problem.

Therefore, the application of a ferrite choke directly targets and mitigates the RF current issue, making