Which term is described by the description 'same key for lock and open'?

Which term is described by the description 'same key for lock and open'?

• A. Encryption
• B. Central processing unit
• C. Symmetric encryption
• D. Asymmetric encryption

Answer: (A)

Using the same key to lock and open is how symmetric encryption works: a single shared secret key is used for both encryption and decryption. This description points to the general process of turning plaintext into ciphertext with a key and then reversing it with the same key. So, the term that best fits the description in the list is encryption, since it refers to the process of encoding data with a key. The other options don’t fit as well: the CPU is not related to cryptography, and asymmetric encryption relies on two different keys rather than the same one.

Using the same key to lock and open is how symmetric encryption works: a single shared secret key is used for both encryption and decryption. This description points to the general process of turning plaintext into ciphertext with a key and then reversing it with the same key. So, the term that best fits the description in the list is encryption, since it refers to the process of encoding data with a key. The other options don’t fit as well: the CPU is not related to cryptography, and asymmetric encryption relies on two different keys rather than the same one.