Which scenario is least likely to prevent a SART's signal from being detected?

The scenario where the SART (Search and Rescue Transponder) is properly mounted while monitoring 3-CM radar is the least likely to prevent the SART's signal from being detected because the characteristics of 3-CM radar are well-suited for detecting SART signals.

SARTs are designed to respond to radar frequencies commonly used over the 3-CM band, which aligns with marine radar systems designed for navigation and rescue operations. When a SART is properly mounted, it has an optimal position and angle for emitting a signal that can be effectively received by rescue vessels or aircraft using radar in this frequency range. The correct positioning minimizes interference and enhances the likelihood of the signal being successfully detected.

In contrast, scenarios where the SART is improperly mounted or where the monitoring radar is not aligned with the optimal frequency for SART operation are more likely to hinder signal detection. Since the 3-CM band is effective for SART communication, this scenario stands out as the most reliable for ensuring that the SART's signal is detected by rescue personnel.