To prevent an unauthorized person from viewing classified information on a computer screen, you must

• A. Follow the Information System's System Security Plan (SSP).
• B. Rely on personal judgment.
• C. Turn off the monitor at all times.
• D. Ignore screen exposure.

Answer: (A)

Preventing unauthorized viewing on a screen comes down to following the documented safeguards for handling classified information. The System Security Plan spells out the approved controls and procedures for display devices, including how access is managed, where and how information can be shown, and what to do if someone might glimpse sensitive data. By adhering to the SSP, you rely on established, auditable requirements rather than personal judgment, ensuring consistent protection across situations. The plan often covers practical measures such as proper screen placement, use of privacy screens, automatic screen locking, and ensuring sessions terminate when not in use. These controls are designed to reduce the risk of shoulder-surfing and casual exposure in real-world environments. Relying on personal judgment can lead to gaps, and turning the monitor off all the time or ignoring screen exposure isn’t a policy-based solution and could still fail to meet required safeguards.