What does Secure Boot configuration support?

A.
Verifying boot media up to and including the boot manager
B.
Signing and verifying UEFI executable files up to and including the boot manager only
C.
Signing and verifying both legacy BIOS and UEFI executable files up to and including the boot
manager
D.
Signing and verifying legacy BIOS executable files up to and including the boot manager only
Explanation: