What does NSF consist of?

The correct answer identifies the Naval Security Force (NSF) as comprising all armed Navy personnel who are assigned to law enforcement and security duties. This includes a range of roles, from Master-at-Arms performing security operations to personnel involved in protection and law enforcement within Navy installations.

NSF is vital for ensuring the safety and security of naval facilities and personnel, which involves a variety of tasks like force protection, response to threats, and law enforcement. The emphasis on "armed Navy personnel" highlights the importance of having trained individuals who can respond to both security and law enforcement challenges effectively.

The other options do not encompass the full scope of NSF. For instance, limiting NSF to only Coast Guard personnel or only administrative or officer personnel overlooks the broad representation of armed personnel across different ranks and assignments critical to the security operations within the Navy. This makes the broader definition provided in the correct answer not just accurate but essential for understanding the composition and responsibilities of the NSF.