Which process will let you start up a Mac in target disk mode?

A.
Hold down the S key on the keyboard while the Mac starts up, then enter the command reboot – target.

B.
Open the Startup Disk preferences, click Target Disk Mode, and then click Restart.

C.
Start up from the OS X Recovery partition, choose Target Disk Mode from the Startup Disk menu, and restart the Mac.

D.
Hold down the Option key on the keyboard as the Mac starts up, until a dialog appears, then select Target Disk Mode from the dialog.