Explanation: The squelch control sets a threshold for the received signal strength. When the squelch is set just beyond the point where background noise disappears, it means the receiver's audio output is muted only for the inherent noise floor. The receiver itself remains at its highest sensitivity, actively listening for any signals on the antenna. This precise squelch setting allows the faintest legitimate signals—those just slightly stronger than the background noise—to open the squelch and be heard. Setting the squelch too high would suppress these weak signals, effectively reducing sensitivity. Therefore, this sweet spot provides maximum sensitivity without the annoyance of constant static. * **A) Maximum sensitivity without background noise.** This is correct. The receiver's ability to detect weak signals is preserved, but the audible noise is eliminated. * **B) Reduced sensitivity without background noise.** Incorrect. This setting *preserves* maximum sensitivity. Reduced sensitivity would occur if the squelch was set much higher. * **C) Minimum background noise with reduced sensitivity.** Incorrect. While background noise is minimized, sensitivity is maintained, not reduced. * **D) Greater bandwidth without background noise.** Incorrect. Squelch has no effect on the receiver's bandwidth, which is determined by internal filtering.