Which marking identifies unencrypted COMSEC keying material used to secure or authenticate telecommunications carrying classified or sensitive information?

• A. CRYPTO
• B. CRYPTOGRAPHIC
• C. COMSEC
• D. KEYING MATERIAL

Answer: (A)

CRYPTO marks indicate that the item contains unencrypted keying material used to secure or authenticate telecommunications carrying classified or sensitive information. This label must be treated with strict COMSEC protection because the material, if exposed, could enable decryption or forgery of communications. The marking tells handlers to follow secure procedures: limit access to cleared personnel, store in approved containers, transmit only by secure means, and destroy using approved methods. Compared to broader labels, such as COMSEC or KEYING MATERIAL, and the term CRYPTOGRAPHIC, CRYPTO specifically signals this unencrypted keying material and the precise handling it requires, making it the most appropriate designation.