, WGU C839 Introduction to Cryptography |OA|
Exam Prep 2026 | 300+ Practice Questions &
Answers | Study Guide
Question 1
What type of encryption uses different keys to encrypt and decrypt a message?
A. Symmetric
B. Private Key
C. Secure
D. Asymmetric
Correct Answer: D. Asymmetric
Rationale
Asymmetric encryption uses a mathematically related public/private key pair. One key encrypts
the data while the other decrypts it. This allows secure communication without sharing secret
keys beforehand.
Question 2
The most widely used asymmetric encryption algorithm is:
A. RSA
B. Vigenère
C. DES
D. Caesar Cipher
Correct Answer: A. RSA
,Rationale
RSA is one of the most widely implemented public-key cryptosystems and is commonly used for
secure key exchange, digital signatures, and certificate-based authentication.
Question 3
Original, unencrypted information is referred to as:
A. Text
B. Plaintext
C. Cleantext
D. Ciphertext
Correct Answer: B. Plaintext
Rationale
Plaintext refers to readable, unencrypted information. Once encryption occurs, plaintext becomes
ciphertext.
Question 4
Which of the following is NOT an asymmetric cryptographic system?
A. PGP
B. RSA
C. SSL/TLS
D. DES
Correct Answer: D. DES
Rationale
, DES is a symmetric block cipher that uses the same key for both encryption and decryption. The
others utilize public-key cryptography components.
Question 5
A security administrator needs to send a confidential message that only User B can read. Which
key should be used to encrypt the message?
A. User A's public key
B. User A's private key
C. User B's public key
D. User B's private key
Correct Answer: C. User B's Public Key
Rationale
Only User B's private key can decrypt data encrypted with User B's public key, ensuring
confidentiality.
Question 6
The greatest weakness of symmetric cryptography is:
A. Lower security
B. Key exchange
C. Slow performance
D. Key generation
Correct Answer: B. Key Exchange
Rationale
Securely distributing secret keys remains the primary challenge of symmetric encryption
systems.
Exam Prep 2026 | 300+ Practice Questions &
Answers | Study Guide
Question 1
What type of encryption uses different keys to encrypt and decrypt a message?
A. Symmetric
B. Private Key
C. Secure
D. Asymmetric
Correct Answer: D. Asymmetric
Rationale
Asymmetric encryption uses a mathematically related public/private key pair. One key encrypts
the data while the other decrypts it. This allows secure communication without sharing secret
keys beforehand.
Question 2
The most widely used asymmetric encryption algorithm is:
A. RSA
B. Vigenère
C. DES
D. Caesar Cipher
Correct Answer: A. RSA
,Rationale
RSA is one of the most widely implemented public-key cryptosystems and is commonly used for
secure key exchange, digital signatures, and certificate-based authentication.
Question 3
Original, unencrypted information is referred to as:
A. Text
B. Plaintext
C. Cleantext
D. Ciphertext
Correct Answer: B. Plaintext
Rationale
Plaintext refers to readable, unencrypted information. Once encryption occurs, plaintext becomes
ciphertext.
Question 4
Which of the following is NOT an asymmetric cryptographic system?
A. PGP
B. RSA
C. SSL/TLS
D. DES
Correct Answer: D. DES
Rationale
, DES is a symmetric block cipher that uses the same key for both encryption and decryption. The
others utilize public-key cryptography components.
Question 5
A security administrator needs to send a confidential message that only User B can read. Which
key should be used to encrypt the message?
A. User A's public key
B. User A's private key
C. User B's public key
D. User B's private key
Correct Answer: C. User B's Public Key
Rationale
Only User B's private key can decrypt data encrypted with User B's public key, ensuring
confidentiality.
Question 6
The greatest weakness of symmetric cryptography is:
A. Lower security
B. Key exchange
C. Slow performance
D. Key generation
Correct Answer: B. Key Exchange
Rationale
Securely distributing secret keys remains the primary challenge of symmetric encryption
systems.
