Which Blu-ray standard defines rewritable disks?

The Blu-ray standard that defines rewritable disks is known as BD-RE. This standard enables users to record data on the media multiple times, allowing for both data storage and editing capabilities. BD-RE disks can be formatted to be compatible with various recording formats, giving users the versatility to use them like traditional hard drives, which can be especially useful for data backups or temporary file storage.

The other choices represent different types of Blu-ray formats: BD-ROM is a read-only format intended primarily for commercial distribution of movies and games and does not allow any data to be rewritten. BD-R is a write-once format where data can be recorded but not modified or erased, making them suitable for archival storage where data integrity is crucial. BD-A is not a standard recognized in relation to Blu-ray technologies, which further clarifies that BD-RE is the specific designation for rewritable Blu-ray disks.