What would most likely prevent a SART's signal from being detected?

Correct Answer: Option D — The rescue personnel were monitoring the 10-cm radar

Search and Rescue Transponders operate exclusively within the 9-GHz (3-cm) marine radar band. Monitoring a 10-cm (S-band) radar instead of a 3-cm (X-band) radar prevents the receiver from detecting the SART's frequency, rendering the electronic locating signal invisible to searching personnel.