Encryption has a remarkably long and varied history.The invention of writing was apparently soon followed by a desire to conceal messages.One of the earliest methods,attributed to an ancient Roman emperor,was the simple substitution of numbers for letters,for example A = 1, B = 2,etc.This is an example of
A) a hashing algorithm.
B) symmetric key encryption.
C) asymmetric key encryption.
D) a public key.

Question

Quizplus · Accepted Answer

The simple substitution of numbers for letters described in the passage is an example of symmetric key encryption, where the same key is used for both encryption and decryption. Hashing algorithms do not involve encryption, and asymmetric key encryption and public keys were not mentioned in the passage.

Encryption Has a Remarkably Long and Varied History