The primary purpose of the GMDSS is to:

The primary purpose of the Global Maritime Distress and Safety System (GMDSS) is to automate and improve emergency communications for the world's shipping industry. GMDSS was established to enhance safety at sea by providing a standardized and reliable means of communication in emergency situations. It integrates various communication methods such as satellite and terrestrial systems to ensure that vessels in distress can quickly send out alerts and receive assistance, regardless of their location or the conditions.

The automation aspect is crucial, as it allows ships to send distress signals automatically without requiring manual intervention from the crew, which is particularly vital in emergencies when quick action is essential. This system also provides for better coordination between ships, coastal stations, and rescue authorities, making it easier to respond to emergencies and save lives at sea.

While other options touch on parts of GMDSS functions, the core aim of enhancing emergency communications through automation distinguishes it as the correct answer.