In the context of disk management, what does the error message "Delete is not allowed on the current boot, system, pagefile, crashdump, or hibernation volume" indicate?
a) The operation to delete a volume is restricted because it is currently in use by essential system functions such as booting or managing memory.
b) The volume is being used for storing personal files, and deletion is restricted to protect data.
c) The volume is encrypted and cannot be deleted without decryption.
d) The volume is corrupted and requires repair before any deletion can occur.