On Cisco IOS XR, for which purpose is the turboboot procedure used?

A.
to boot the router into ROM Monitor mode

B.
to install the IOS XR software from scratch using the ROM Monitor mode

C.
to install and boot up a PIE

D.
to install and boot up a SMU

E.
to perform an ISSU

F.
to speed up the time it takes to boot up the IOS XR router