What action is required when a mobile device is outside the operator's coverage area?

Roaming is the process that allows a mobile device to access networks outside of its operator's coverage area. When a user travels beyond the geographical limits of their mobile network provider, roaming enables the device to connect to a partner or alternative network that may offer service in that area. This ensures that users can maintain connectivity even when they are not within their home network's coverage, which is essential for making calls, sending messages, and using data services.

While other choices suggest potential responses to a lack of coverage, they do not address the fundamental need for connectivity outside of the operator's network. Increasing the power supply or looking for a better place may not resolve the issue of coverage itself, and getting a better quality mobile phone does not guarantee improved access in areas lacking signal. Roaming is specifically designed to address the challenge of maintaining communication when a user's mobile device is out of the operator's coverage, making it the only viable solution among the options provided.