Is implemented by identifying inmates who are of particular concern to public safety and by providing those specific offenders with much longer sentences than would be given to other inmates.

The answer is "selective incapacitation".

Explanation:

Incapacitation stands for when a person commits his crime. Selective incapacitation is a disciplinary mechanism, that preserves communities and only imprisoning criminals, who pose the biggest threat to society.  

The danger is related to the quality and variety of offenses and the risk of re-infraction. It stops the significant number of crimes, even low-end tests say.  The most economical disability approach will require more narrowly the redistribution of penal services by defining the most violent offender selective incapacitation.  

Iwould go with either b or c, not sure which one.

Yes, by adjusting the boot order.