What configuration setting determines whether the sync process starts automatically when the app gets online?

The configuration setting that determines whether the sync process starts automatically when the app gets online is "SyncOnOnline." This setting is specifically designed to trigger the synchronization of data as soon as the application detects an internet connection. This ensures that users receive the most up-to-date information without requiring any manual intervention from their side once the app regains connectivity.

In mobile applications, it's critical to manage data synchronization efficiently, especially in scenarios where users frequently shift between online and offline environments. By enabling the SyncOnOnline configuration, developers provide a seamless experience for users, ensuring that they are always working with current data.

The other options, while related to syncing, do not specifically address the requirement of initiating synchronization upon regaining an online status. For example, "SyncOnLogin" pertains to syncing when a user logs into the app, and "SyncOnResume" relates to syncing when the app comes back into focus. "RetryOfError" deals with retries after a sync failure rather than the initiation of the sync process itself. Thus, "SyncOnOnline" is the most appropriate choice for this specific functionality.