Explanation: COSPAS-SARSAT satellites are primarily signal relays and position-determining platforms, not direct providers of search and rescue (SAR) operations or follow-on services. While they detect distress signals, calculate positions, and forward information, the actual rescue effort is coordinated by ground-based Mission Control Centers (MCCs) and Rescue Coordination Centers (RCCs) after receiving the alert. Therefore, the satellites themselves do not "provide follow-on" services. Options A, B, and C describe actual functions of the COSPAS-SARSAT system: * **A)** The EPIRB ID is crucial for identifying the distressed vessel and retrieving associated registration data, which is vital for SAR. * **B)** Low Earth Orbit (LEO) COSPAS-SARSAT satellites use the Doppler shift of the EPIRB's signal to calculate its position, especially for EPIRBs without integrated GPS. * **C)** Satellites time-tag received distress information and transmit it to ground stations known as Local User Terminals (LUTs) for processing and forwarding.