A character string used in cryptography to code or decode a message in a cryptography algorithm is called a...

• A. Cryptographic Key
• B. Cryptography
• C. Cyberbullying
• D. Cyberwarfare

Answer: (A)

The concept is that a cryptographic key is the piece of information that controls how a message is transformed during encryption and how it is reversed during decryption. A character string used to code or decode a message fits this definition exactly because the key determines which transformation the plaintext undergoes to become ciphertext and which transformation changes it back. In symmetric systems, the same key is used to both encrypt and decrypt; in asymmetric systems, a private key is used for decryption while a public key is used for encryption. The other terms don’t describe this mechanism: cryptography is the overall field, while cyberbullying and cyberwarfare refer to harmful activities, not the data that encodes or decodes messages.