Nearly all encryption for confidentiality uses which type of encryption ciphers?

• A. Public key
• B. Symmetric key
• C. Hashing
• D. None of the above

Answer: (B)

Protecting the privacy of the content relies on using a cipher that can efficiently hide data with a shared secret. Symmetric key ciphers use the same key to encrypt and decrypt, which makes them fast and practical for securing large amounts of data. Public-key (asymmetric) encryption is slower and is usually reserved for exchanging keys or for digital signatures, not bulk confidentiality. Hashing isn’t encryption at all; it’s a one-way function used to verify integrity, not to conceal content. In practice, systems often combine both: a random symmetric key protects the data, and that key is secured with public-key cryptography when sending it over an insecure channel.