Which of these isn't a thing?

Which of these isn't a thing?

• D2D2T
• LTO-5
• D2T
• LOT2 

EXPLANATION

 Disk-to-disk-to-tape (D2D2T) is a data storage and backup technique where data is backed up on a disk before it is copied to a backup tape device. This databackup process temporarily first stores the primary disk content to another diskand then to the backup tape device.

Linear Tape-Open (LTO) is a magnetic tape data storage technology originally developed in the late 1990s as an open standards alternative to the proprietary magnetic tape formats that were available at the time. ... LTO is widely used with small and large computer systems, especially for backup.

Dist to tape (D2T) is a backup methodology in which data is backed up directly from a disk (typically a hard disk) to a magnetic tape. This process is widely applied in enterprises where the archival stability is critical, allowing a disaster recovery plan to recover data