If you only have a GED you are assigned as the A.
If you can't see and are forgetful, you are assigned as the B.
If you smash your fingers with a hammer while driving a nail, you are a C.
If you are snarly and hate everyone and just don't give a shit, you are the D.
If you are tone deaf, have tinnitus, hard of hearing, you are a E.
If you are just stupid low IQ fuck-up, you are a F.
If you are the cherry on the team, you are the Z.
Follow this and you'll go far, just not in SF.