Which statement is true regarding the operation of the navigation radios?

The statement regarding the operation of navigation radios being true is that white needles must display for optimal navigation. In aviation, especially in the context of navigation radios, optimal navigation relies on proper tuning and indication of the navigation signals. The white needles refer to the indicators on the navigation display that provide a visual representation of the aircraft's position relative to a navigation aid, such as a VOR (VHF Omnidirectional Range) or an ILS (Instrument Landing System). For pilots to accurately navigate, these indicators must show the correct data, and it is crucial for maintaining situational awareness and ensuring safe approach and landing procedures.

When the white needles are correctly displayed, it indicates that the navigation system is receiving signals appropriately from the ground-based navigation aids, allowing the crew to effectively determine and maintain their flight path. Proper indication is vital during phases of flight such as approach and landing when accurate navigation is essential for safety.