单选题A large corporation is concerned about the amount of time it takes to back up their main file server. They are also concerned that their IT technician frequently forgets to change the backup tapes， thereby leaving the company open to data loss. Which b

A large corporation is concerned about the amount of time it takes to back up their main file server. They are also concerned that their IT technician frequently forgets to change the backup tapes， thereby leaving the company open to data loss. Which backup system would solve both problems？（）