In designing an IoT device that must operate reliably on intermittent or unreliable cellular connectivity (e.g., NB-IoT), what architectural pattern helps ensure data is not lost during outages?

A Local buffering/queuing of data on the device during connectivity loss, with retry and acknowledgment logic to upload buffered data once connectivity is restored B The device should immediately discard all data the instant connectivity is lost, with no retry C Intermittent connectivity has no impact on data integrity and requires no special handling D The device should permanently stop collecting any sensor data if the network is ever unavailable