Which scenario outlines a proper handling procedure for classified information?

Storing classified materials in locked cabinets is indeed a proper handling procedure for classified information. This practice is essential for ensuring the security and integrity of sensitive information. By keeping classified materials in a locked cabinet, access is restricted to authorized personnel only, which helps prevent unauthorized access, tampering, or disclosure of sensitive data.

This method adheres to protocols that require physical security measures for materials deemed classified, thus safeguarding national security interests. Proper storage in locked environments minimizes the risk of accidental exposure or loss, which is a critical aspect of maintaining the confidentiality of classified information.

In contrast, the other scenarios violate established security protocols. Leaving documents unguarded, discussing sensitive information in public, and mixing classified with unclassified documents all expose classified data to potential risks, undermining the goal of safeguarding sensitive information.