Final answer:
The "Cabin Pressure" aural warning is triggered by a loss of cabin pressure, alerting the crew to a potentially dangerous situation. This specific warning is for cabin pressure and not for other issues such as temperature, landing gear, or fuel levels.
Step-by-step explanation:
The "Cabin Pressure" aural warning in an aircraft is activated when there is a loss in cabin pressure. This is an important safety feature designed to alert the pilots and crew when the atmospheric pressure within the cabin falls below a safe threshold. Loss of cabin pressure can be dangerous as it may lead to hypoxia, where individuals on board the aircraft experience a deficiency in the amount of oxygen reaching their tissues. The other options listed, such as exceeding a certain cabin temperature, deployment of the landing gear, or critically low fuel levels, have their own specific warning signals and are not related to the cabin pressure warning system. Understanding this aspect of aircraft operation is critical, as evident from historical incidents where attention to detail regarding measurements and units has led to near disasters, emphasizing the importance of precision and awareness in aviation.