2026/2027
WGU D330 Intro to Cryptography
OA Final Exam Prep and Test Bank
Review 2026/2027: Complete
Assessment Guide with Quizzes, Key
Concepts, and Exam-Style Questions
Question 1
What type of encryption uses different keys to encrypt and decrypt the message?
A. Symmetric
B. Private key
C. Secure
D. Asymmetric
Correct Answer: D. Asymmetric
Rationale:
Asymmetric encryption uses a pair of mathematically related keys: a public key for
encryption and a private key for decryption. This allows secure communication
without sharing a secret key beforehand. Symmetric encryption, by contrast, uses the
same key for both encryption and decryption, making key distribution a major
challenge. The other options are either incorrect terminology or non-standard
classifications in cryptography.
Question 2
The most widely used asymmetric encryption algorithm is what?
A. RSA
B. Vigenère
C. DES
D. Caesar Cipher
Correct Answer: A. RSA
Rationale:
RSA is the most widely adopted asymmetric algorithm due to its strong mathematical
foundation in prime factorization and its practical use in encryption, digital signatures,
and secure key exchange. Vigenère and Caesar are classical ciphers and not secure for
modern use, while DES is a symmetric encryption algorithm, not asymmetric.
,2026/2027
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 data in its original, readable form before encryption. Ciphertext is
the transformed, unreadable output after encryption. The other options are not
standard cryptographic terms used in professional or academic contexts.
Question 4
Which of the following is NOT an asymmetric system?
A. PGP
B. RSA
C. SSL
D. DES
Correct Answer: D. DES
Rationale:
DES (Data Encryption Standard) is a symmetric encryption algorithm using a single
shared key. RSA and PGP rely on asymmetric cryptography, while SSL uses
asymmetric methods during handshake before switching to symmetric encryption for
data transfer.
Question 5
In order for User A to send User B an encrypted message that only User B can read,
User A must encrypt the message with which key?
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:
In asymmetric encryption, a sender encrypts data using the recipient’s public key.
,2026/2027
Only the recipient’s private key can decrypt the message, ensuring confidentiality.
Using User A’s keys would not restrict access to User B, and private keys are never
used for encrypting messages for others.
Question 6
The greatest weakness with symmetric algorithms is ____.
A. They are less secure than asymmetric
B. The problem of key exchange
C. They are slower than asymmetric
D. The problem of generating keys
Correct Answer: B. The problem of key exchange
Rationale:
Symmetric encryption is fast and secure, but both parties must share the same secret
key. Securely exchanging this key over an insecure channel is the primary
vulnerability. The other options are incorrect because symmetric algorithms are
generally faster, not slower, and are not inherently less secure.
Question 7
Which of the following is generally true about block sizes?
A. Smaller block sizes increase security
B. Block sizes must be more than 256 bits
C. Block size is irrelevant to security
D. Larger block sizes increase security
Correct Answer: D. Larger block sizes increase security
Rationale:
Larger block sizes reduce patterns in encrypted data and make cryptanalysis more
difficult, improving resistance to attacks. Smaller blocks may reveal patterns,
weakening security. Block size is therefore a significant factor in modern
cryptographic strength.
Question 8
A _____ is a function that takes a variable-size input m and returns a fixed-size string.
A. Symmetric cipher
B. Hash
C. Asymmetric cipher
D. Feistel
, 2026/2027
Correct Answer: B. Hash
Rationale:
A cryptographic hash function processes input data of any size and produces a fixed-
length output known as a digest. This output is deterministic but irreversible. The
other options describe encryption structures, not hashing functions.
Question 9
Which of the following is a cryptographic protocol that allows two parties to establish
a shared key over an insecure channel?
A. Elliptic Curve
B. RSA
C. MD5
D. Diffie-Hellman
Correct Answer: D. Diffie-Hellman
Rationale:
Diffie-Hellman enables two parties to securely generate a shared secret key over an
insecure network without transmitting the key itself. RSA is an encryption algorithm,
MD5 is a hash function, and elliptic curve refers to a mathematical approach used in
multiple cryptographic systems.
Question 10
A digital representation of information that identifies you as a relevant entity by a
trusted third party is called ____.
A. Digital Signature
B. Hash
C. Ownership stamp
D. Digest
Correct Answer: A. Digital Signature
Rationale:
A digital signature verifies identity and ensures message integrity using asymmetric
cryptography. It is issued by a trusted authority and binds identity to data. Hashes and
digests only represent data integrity, not identity.
Question 11
What is the standard used by most digital certificates?
WGU D330 Intro to Cryptography
OA Final Exam Prep and Test Bank
Review 2026/2027: Complete
Assessment Guide with Quizzes, Key
Concepts, and Exam-Style Questions
Question 1
What type of encryption uses different keys to encrypt and decrypt the message?
A. Symmetric
B. Private key
C. Secure
D. Asymmetric
Correct Answer: D. Asymmetric
Rationale:
Asymmetric encryption uses a pair of mathematically related keys: a public key for
encryption and a private key for decryption. This allows secure communication
without sharing a secret key beforehand. Symmetric encryption, by contrast, uses the
same key for both encryption and decryption, making key distribution a major
challenge. The other options are either incorrect terminology or non-standard
classifications in cryptography.
Question 2
The most widely used asymmetric encryption algorithm is what?
A. RSA
B. Vigenère
C. DES
D. Caesar Cipher
Correct Answer: A. RSA
Rationale:
RSA is the most widely adopted asymmetric algorithm due to its strong mathematical
foundation in prime factorization and its practical use in encryption, digital signatures,
and secure key exchange. Vigenère and Caesar are classical ciphers and not secure for
modern use, while DES is a symmetric encryption algorithm, not asymmetric.
,2026/2027
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 data in its original, readable form before encryption. Ciphertext is
the transformed, unreadable output after encryption. The other options are not
standard cryptographic terms used in professional or academic contexts.
Question 4
Which of the following is NOT an asymmetric system?
A. PGP
B. RSA
C. SSL
D. DES
Correct Answer: D. DES
Rationale:
DES (Data Encryption Standard) is a symmetric encryption algorithm using a single
shared key. RSA and PGP rely on asymmetric cryptography, while SSL uses
asymmetric methods during handshake before switching to symmetric encryption for
data transfer.
Question 5
In order for User A to send User B an encrypted message that only User B can read,
User A must encrypt the message with which key?
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:
In asymmetric encryption, a sender encrypts data using the recipient’s public key.
,2026/2027
Only the recipient’s private key can decrypt the message, ensuring confidentiality.
Using User A’s keys would not restrict access to User B, and private keys are never
used for encrypting messages for others.
Question 6
The greatest weakness with symmetric algorithms is ____.
A. They are less secure than asymmetric
B. The problem of key exchange
C. They are slower than asymmetric
D. The problem of generating keys
Correct Answer: B. The problem of key exchange
Rationale:
Symmetric encryption is fast and secure, but both parties must share the same secret
key. Securely exchanging this key over an insecure channel is the primary
vulnerability. The other options are incorrect because symmetric algorithms are
generally faster, not slower, and are not inherently less secure.
Question 7
Which of the following is generally true about block sizes?
A. Smaller block sizes increase security
B. Block sizes must be more than 256 bits
C. Block size is irrelevant to security
D. Larger block sizes increase security
Correct Answer: D. Larger block sizes increase security
Rationale:
Larger block sizes reduce patterns in encrypted data and make cryptanalysis more
difficult, improving resistance to attacks. Smaller blocks may reveal patterns,
weakening security. Block size is therefore a significant factor in modern
cryptographic strength.
Question 8
A _____ is a function that takes a variable-size input m and returns a fixed-size string.
A. Symmetric cipher
B. Hash
C. Asymmetric cipher
D. Feistel
, 2026/2027
Correct Answer: B. Hash
Rationale:
A cryptographic hash function processes input data of any size and produces a fixed-
length output known as a digest. This output is deterministic but irreversible. The
other options describe encryption structures, not hashing functions.
Question 9
Which of the following is a cryptographic protocol that allows two parties to establish
a shared key over an insecure channel?
A. Elliptic Curve
B. RSA
C. MD5
D. Diffie-Hellman
Correct Answer: D. Diffie-Hellman
Rationale:
Diffie-Hellman enables two parties to securely generate a shared secret key over an
insecure network without transmitting the key itself. RSA is an encryption algorithm,
MD5 is a hash function, and elliptic curve refers to a mathematical approach used in
multiple cryptographic systems.
Question 10
A digital representation of information that identifies you as a relevant entity by a
trusted third party is called ____.
A. Digital Signature
B. Hash
C. Ownership stamp
D. Digest
Correct Answer: A. Digital Signature
Rationale:
A digital signature verifies identity and ensures message integrity using asymmetric
cryptography. It is issued by a trusted authority and binds identity to data. Hashes and
digests only represent data integrity, not identity.
Question 11
What is the standard used by most digital certificates?
