When an operating system marks a cluster as used but not allocated, the cluster is considered as which of the following?

When an operating system marks a cluster as used but not allocated, the cluster is considered as which of the following?

• A. Corrupt
• B. Bad
• C. Lost
• D. Unallocated

Answer: (C)

Clusters are the basic units the file system uses to track disk space. When a cluster is marked as used, it’s not free, but if there’s no file entry or directory pointer that owns that cluster, it isn’t part of any file. That situation creates an orphaned cluster, commonly called a lost cluster. It’s effectively allocated in the filesystem’s metadata but not linked to any file, so it’s not accessible through normal file system navigation. This is why lost cluster is the correct choice: it describes data that the system believes is in use, yet has no owner file. The other terms don’t fit: a bad cluster is unusable hardware-marked; a corrupt cluster implies broader integrity problems; unallocated means free space.

Clusters are the basic units the file system uses to track disk space. When a cluster is marked as used, it’s not free, but if there’s no file entry or directory pointer that owns that cluster, it isn’t part of any file. That situation creates an orphaned cluster, commonly called a lost cluster. It’s effectively allocated in the filesystem’s metadata but not linked to any file, so it’s not accessible through normal file system navigation. This is why lost cluster is the correct choice: it describes data that the system believes is in use, yet has no owner file. The other terms don’t fit: a bad cluster is unusable hardware-marked; a corrupt cluster implies broader integrity problems; unallocated means free space.