A cluster can also be known as what?

The term "cluster" refers to a group of sectors on a disk that are managed as a single unit for storing files. In the context of file systems, options like logical partition, master track, and extended partition represent different concepts but do not accurately describe the role that a cluster plays in file storage.

A file allocation unit is the best fit among the provided choices because it directly relates to how files are organized and stored on a disk. Clusters serve as the smallest unit of disk space allocation for files; a file may occupy one or more clusters depending on its size. Thus, understanding clusters as file allocation units is essential for comprehending disk management and file system architecture. Clusters help optimize storage by allowing efficient use of disk space, reducing fragmentation, and improving read/write performance.