What should flight attendants do upon noticing a suspicious package on board?

When a flight attendant notices a suspicious package on board, the most appropriate action is to notify the captain and follow established security protocols. This is critical for ensuring the safety of all passengers and crew on the flight.

Flight attendants are trained to recognize items or situations that could pose a security threat, and promptly informing the captain allows for the situation to be assessed by someone who has the authority to make decisions about passenger safety and security measures. Following security protocols ensures that there is a systematic response to any potential threat, which is vital in maintaining a safe environment in the aircraft.

Handling the package carefully or asking passengers about its ownership may inadvertently escalate a situation or compromise safety. Ignoring the package can lead to severe consequences if it is indeed hazardous. Hence, the response involving notifying the captain and adhering to security guidelines is the correct and most responsible option.