What is the action of changing a message into another format through the use of a code?

• A. Encryption
• B. Encoding
• C. Obfuscation
• D. Compression

Answer: (A)

Encryption is the process of converting a message into another format that is unreadable to anyone without the proper key, using a cipher. This transformation hides the content and preserves confidentiality because only someone with the key can reverse it and recover the original message. Encoding, on the other hand, changes data into another representation for transmission or storage without concealing meaning; it’s easily reversible and not intended for security. Obfuscation hides intent or makes analysis harder but isn’t a formal cryptographic protection, and compression reduces size, which has nothing to do with securing the content. So the described action best fits encryption.