How should classified information be protected when shared in electronic format?

The correct choice emphasizes the importance of both marking and encrypting classified information in compliance with established policies. When sharing classified information electronically, it is crucial to adhere to specific guidelines that ensure the sensitivity of the data is clearly communicated and properly protected against unauthorized access.

Marking classified information serves to inform recipients about the classification level and handling requirements, which is essential for maintaining security protocols. Encryption, on the other hand, provides a layer of protection that secures the information from interception during transmission. Both actions are necessary to mitigate risks associated with electronic communications.

Together, marking and encrypting classified information provide a comprehensive approach to safeguarding sensitive data, ensuring that it is both visibly identified and protected from potential threats. This combination aligns with best practices and regulatory requirements for handling classified information in the digital realm.