A User Turns on Her Computer,and a Message Warns the User

Multiple Choice

A user turns on her computer,and a message warns the user that the date and time are not set.Which of the following is the most probable cause?

A) Operating system is in need of system updates
B) CMOS battery needs to be replaced
C) BIOS needs an upgrade
D) Boot sequence is pointing to the CD-ROM drive and attempting to boot from it