How does unallocated space differ from unused space? a$.$ Unallocated space is $$Free Space$$ while unused isn$$t accessible through the operating system b$.$ Unallocated space is $$Free Space$$ while unused space is the portion of the disk that hasn$$t been written to c$.$ Unallocated space is the portion of the disk that files have been written to while unused space is the portion of the disk that hasn$$t been written to d$.$ Unallocated space is no longer allocated because of an erased or deleted file while unused is $$Free space$$