The Caesar cipher is the oldest known encryption method.

• A. True
• B. False
• C. It depends on definitions
• D. Not enough information

Answer: (A)

Historically, the Caesar cipher is described as one of the earliest encryption techniques with a clearly defined method: shifting letters by a fixed amount. It’s tied to Julius Caesar and his practice of coding messages, which makes it a foundational example in early cryptography. While older devices like the Scytale and other ancient methods existed, Caesar cipher is commonly presented as the oldest known encryption method with a well-defined algorithm, which is why this statement is the best answer.