1
WGU C839V5/D334 Exam 2025/2026 –
Passed Questions with Verified Correct
Answers (100% Guaranteed Success)
Question 1
What are the two main types of symmetric ciphers?
A. Block and Stream
B. DES and AES
C. Active and Passive
D. RSA and ECC
A. Block and Stream
Rationale: Symmetric ciphers are divided into block ciphers, which encrypt fixed -size
blocks of data, and stream ciphers, which encrypt data as a continuous stream. DES and AES are
specific algorithms, not types, while RSA and ECC are asymmetric.
Question 2
In asymmetric cryptography, which key is shared to facilitate decryption?
A. Private key
B. Secret key
C. Public key
D. Session key
C. Public key
Rationale: In asymmetric cryptography, the public key is shared to encrypt data, which can
only be decrypted by the corresponding private key, ensuring secure communication.
Question 3
Which algorithm is used for secure key exchange in asymmetric cryptography?
A. AES
B. Diffie-Hellman
C. SHA-256
D. MD5
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B. Diffie-Hellman
Rationale: Diffie-Hellman is a key exchange algorithm that allows secure sharing of
cryptographic keys over an insecure channel, commonly used in asymmetric systems. AES is
symmetric, and SHA-256 and MD5 are hashing algorithms.
Question 4
RC4 is a symmetric block cipher used with SSL and WEP. True or False?
A. True
B. False
B. False
Rationale: RC4 is a symmetric stream cipher, not a block cipher, historically used with SSL
and WEP but considered insecure due to vulnerabilities.
Question 5
Which of the following are stream ciphers? (Select all that apply.)
A. ChaCha
B. RC2
C. IDEA
D. RC4
A. ChaCha, D. RC4
Rationale: ChaCha and RC4 are stream ciphers, encrypting data as a continuous stream.
RC2 and IDEA are block ciphers, processing fixed-size data blocks.
Question 6
What manages how blocks of data are processed in symmetric encryption?
A. Stream ciphers
B. Block cipher modes
C. Padding schemes
D. Key schedules
B. Block cipher modes
Rationale: Block cipher modes (e.g., ECB, CBC) determine how blocks of data are
processed in symmetric encryption to ensure security and efficiency.
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Question 7
Which block cipher mode encrypts each block independently?
A. Cipher Block Chaining (CBC)
B. Electronic Code Book (ECB)
C. Counter (CTR)
D. Output Feedback (OFB)
B. Electronic Code Book (ECB)
Rationale: ECB encrypts each block independently using the same key, making it simple but
less secure due to identical plaintext producing identical ciphertext.
Question 8
Which block cipher mode uses an initialization vector (IV) to enhance security?
A. Electronic Code Book (ECB)
B. Cipher Block Chaining (CBC)
C. Galois/Counter Mode (GCM)
D. Both B and C
D. Both B and C
Rationale: CBC and GCM use an initialization vector to introduce randomness, enhancing
security by ensuring unique ciphertext even for identical plaintext.
Question 9
What is the block size of the AES algorithm?
A. 64 bits
B. 128 bits
C. 256 bits
D. Variable
B. 128 bits
Rationale: AES (Advanced Encryption Standard) uses a fixed block size of 128 bits, with
key sizes of 128, 192, or 256 bits, ensuring robust encryption.
Question 10
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WGU C839V5/D334 Exam 2025/2026 –
Passed Questions with Verified Correct
Answers (100% Guaranteed Success)
Question 1
What are the two main types of symmetric ciphers?
A. Block and Stream
B. DES and AES
C. Active and Passive
D. RSA and ECC
A. Block and Stream
Rationale: Symmetric ciphers are divided into block ciphers, which encrypt fixed -size
blocks of data, and stream ciphers, which encrypt data as a continuous stream. DES and AES are
specific algorithms, not types, while RSA and ECC are asymmetric.
Question 2
In asymmetric cryptography, which key is shared to facilitate decryption?
A. Private key
B. Secret key
C. Public key
D. Session key
C. Public key
Rationale: In asymmetric cryptography, the public key is shared to encrypt data, which can
only be decrypted by the corresponding private key, ensuring secure communication.
Question 3
Which algorithm is used for secure key exchange in asymmetric cryptography?
A. AES
B. Diffie-Hellman
C. SHA-256
D. MD5
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, 2
B. Diffie-Hellman
Rationale: Diffie-Hellman is a key exchange algorithm that allows secure sharing of
cryptographic keys over an insecure channel, commonly used in asymmetric systems. AES is
symmetric, and SHA-256 and MD5 are hashing algorithms.
Question 4
RC4 is a symmetric block cipher used with SSL and WEP. True or False?
A. True
B. False
B. False
Rationale: RC4 is a symmetric stream cipher, not a block cipher, historically used with SSL
and WEP but considered insecure due to vulnerabilities.
Question 5
Which of the following are stream ciphers? (Select all that apply.)
A. ChaCha
B. RC2
C. IDEA
D. RC4
A. ChaCha, D. RC4
Rationale: ChaCha and RC4 are stream ciphers, encrypting data as a continuous stream.
RC2 and IDEA are block ciphers, processing fixed-size data blocks.
Question 6
What manages how blocks of data are processed in symmetric encryption?
A. Stream ciphers
B. Block cipher modes
C. Padding schemes
D. Key schedules
B. Block cipher modes
Rationale: Block cipher modes (e.g., ECB, CBC) determine how blocks of data are
processed in symmetric encryption to ensure security and efficiency.
Page 2 of 19
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Question 7
Which block cipher mode encrypts each block independently?
A. Cipher Block Chaining (CBC)
B. Electronic Code Book (ECB)
C. Counter (CTR)
D. Output Feedback (OFB)
B. Electronic Code Book (ECB)
Rationale: ECB encrypts each block independently using the same key, making it simple but
less secure due to identical plaintext producing identical ciphertext.
Question 8
Which block cipher mode uses an initialization vector (IV) to enhance security?
A. Electronic Code Book (ECB)
B. Cipher Block Chaining (CBC)
C. Galois/Counter Mode (GCM)
D. Both B and C
D. Both B and C
Rationale: CBC and GCM use an initialization vector to introduce randomness, enhancing
security by ensuring unique ciphertext even for identical plaintext.
Question 9
What is the block size of the AES algorithm?
A. 64 bits
B. 128 bits
C. 256 bits
D. Variable
B. 128 bits
Rationale: AES (Advanced Encryption Standard) uses a fixed block size of 128 bits, with
key sizes of 128, 192, or 256 bits, ensuring robust encryption.
Question 10
Page 3 of 19
