Explanation: The internationally recognized Urgency signal is "PAN PAN," spoken three times before the urgency call. This radiotelephony signal indicates that the transmitting station has a very urgent message concerning the safety of a ship, aircraft, or person, but does not require immediate assistance. It signifies a lower level of severity than a distress call. A) "TTT" transmitted three times is the internationally recognized urgency signal for radiotelegraphy (Morse code), not radiotelephony. C) Three oral repetitions of the word “Safety” is not a recognized signal. The international safety signal for radiotelephony is "SECURITE" (pronounced Say-cure-e-tay), repeated three times. D) The pronouncement of the word "Mayday" is the internationally recognized *distress* signal, indicating grave and imminent danger requiring immediate assistance, which is distinct from an urgency situation.