When Backing Up a Database Server to LTO Tape Drives

When backing up a database server to LTO tape drives, the following backup schedule is used. Backups take one hour to complete: On Friday at 9:00 p.m., there is a RAID failure on the database server. The data must be restored from backup. Which of the following is the number of backup tapes that will be needed to complete this operation?

A) 1
B) 2
C) 3
D) 4
E) 6