You receive a “Storage Almost Full " alert on your iPhone.

When an iPhone displays a Storage Almost Full alert, Apple recommends reviewing the storage recommendations available in Settings > General > iPhone Storage. These recommendations can identify opportunities to optimize storage, such as offloading unused apps, reviewing large attachments, or removing unnecessary content. Therefore, option D is correct. Erasing all content and settings is unnecessarily destructive and is not an appropriate first response to low storage. Turning off iCloud Backup does not meaningfully free the iPhone’s local storage because iCloud storage and device storage are separate. System Data also cannot normally be manually cleared through a dedicated “Clear System Data” control. Reviewing Apple’s built-in storage recommendations provides the safest and most targeted way to recover space.

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