Joseph enabled FileVault 2. He then forgot the administrator password. How can you help Joseph?

A.
Ask Joseph to startup from OS X Recovery and choose

B.
Have Joseph startup from OS X Recovery and open the Firmware Password utility

C.
Explain to Joseph that he can unlock the disk using the recovery key created when FileVault 2 was enabled.

D.
Help Joseph erase the hard disk and reinstall OS X and forgotten.