If the DME at PUC airport is inoperative, what will the airborne DME transmit?

When the Distance Measuring Equipment (DME) at PUC airport is inoperative, the airborne DME will not produce any audio tone. This is because the primary function of DME is to provide pilots with distance information based on ground station signals, which are required for the system to operate correctly. If the ground station is not operational, the airborne DME cannot effectively relay the corresponding distance measurements or provide the necessary audio identification tone that pilots typically use for navigation confirmation. Hence, an inoperative DME results in no audio output, making the choice regarding the absence of an audio tone the accurate one.

The other options do not align with the operations of DME in an inoperative state, as there would indeed be no coded identification audio or visual identification presented to the pilot, nor would the system be able to provide navigational information without functional support from the ground station.