Which of the following devices is specifically designed for individual distress signals?

The correct answer, the Personal Locator Beacon (PLB), is specifically designed for individual distress signals and is intended for personal use by individuals in emergency situations. PLBs transmit a unique signal that includes the user's registration information to search and rescue organizations via satellite networks. This allows rescuers to pinpoint the user's location promptly, often leading to a faster response and improved chances of survival.

On the other hand, while Emergency Locator Transmitters (ELTs) and Emergency Position Indicating Radio Beacons (EPIRBs) are also used for distress signaling, they are generally designed for use on aircraft and ships, respectively. ELTs are installed in aircraft and activate automatically upon crash landing, while EPIRBs are made for marine use, activated in the event of a vessel emergency. Both of these devices are more oriented toward specific operational environments rather than individual personal distress situations.

Thus, the PLB stands out as it is portable, easily activated by an individual, and specifically targets personal emergency scenarios, making it the most appropriate choice in this context.