How should crew members address a bomb threat?

In the case of a bomb threat, crew members must prioritize the safety of everyone on board and adhere to established protocols. The correct response is to follow those protocols and promptly notify the appropriate authorities, which may include security personnel, law enforcement, or emergency services. This ensures that the situation is handled by trained professionals who can assess the threat and take appropriate action.

Established protocols typically include specific procedures for communication, evacuation, and securing the aircraft. By following these guidelines, crew members help to maintain order and ensure that the situation is managed effectively. Immediate communication with the proper authorities is vital in assessing potential risks and implementing necessary security measures to protect passengers and crew.

The other options suggest actions that could compromise safety. For instance, informing passengers immediately might create panic or disrupt procedures. Ignoring the threat poses a significant risk to lives if the threat is valid. Waiting for further instructions from ground staff can delay necessary actions and communication, which is detrimental in an emergency situation. Thus, adhering to established protocols is the most responsible and effective course of action in the face of a bomb threat.