Explanation: Minimizing RF interference involves a multifaceted approach to prevent unwanted radio frequency energy from radiating or coupling into sensitive circuits. A) **Brush by-pass capacitors** are essential in devices with motors, such as power tools. They shunt the high-frequency electrical noise generated by sparking brushes directly to ground. This prevents the noise from propagating along power lines or radiating into the environment as RF interference. B) **Filters**, including low-pass and high-pass types, are designed to attenuate unwanted frequencies. For example, a low-pass filter can block higher-frequency RF noise from a power supply, allowing only the desired lower frequencies to pass. Conversely, a high-pass filter might block strong lower-frequency broadcast signals from interfering with higher-frequency amateur reception. C) **Shielding** of long connecting leads is critical because unshielded wires can act as efficient antennas, both radiating internal RF energy and picking up external RF signals. A conductive shield surrounding the lead contains internal electromagnetic fields and diverts external fields to ground, significantly reducing coupling and interference. Since each of these methods effectively addresses different sources and propagation paths of RF interference, employing "All of the above" represents a comprehensive strategy for mitigation.