The statement 'Nearly all encryption for confidentiality uses symmetric key encryption ciphers' is true.

• A. True
• B. False
• C. Depends on the context
• D. Not specified

Answer: (A)

For confidentiality, the main practical mechanism is using symmetric-key ciphers because they are fast and efficient at encrypting large amounts of data. In real-world systems, data is usually encrypted with a symmetric algorithm (like AES) while a public-key method is employed only to securely exchange the symmetric key or to provide authentication. This hybrid approach lets you get the performance benefits of symmetric encryption while still enabling secure key distribution. So the statement is true: almost all encryption for confidentiality relies on symmetric ciphers for the actual data, with asymmetric methods assisting in key management rather than replacing the need for symmetric encryption. The other options aren’t a better fit because, in practice, key exchange and identity are handled by asymmetric cryptography, but the burden of encrypting the content itself falls to symmetric ciphers.