CompTIA Security+ (SY0-501) — Question 787

When an initialization vector is added to each encryption cycle, it is using the:

Answer options

• A. ECB cipher mode
• B. MD5 cipher mode
• C. XOR cipher mode
• D. CBC cipher mode

Correct answer: D

Explanation

The correct answer is D, CBC cipher mode, as it utilizes an initialization vector to enhance security by ensuring that the same plaintext will encrypt to different ciphertexts. The other options do not employ an initialization vector in their encryption processes: ECB mode lacks it, MD5 is a hashing algorithm, and XOR cipher mode is a simple operation that does not involve IVs.