WGU D334 INTRO TO CRYPTOGRAPHY PA QUESTIONS
AND CORRECT ANSWERS PLUS RATIONALE
(ALREADY GRADED A+) LATEST 2026-2027 UPDATE
50 QUESTIONS
TABLE OF CONTENTS
# TOPIC
1 Analyze and compare symmetric and asymmetric cryptographic algorithms and their appropriate use
cases
2 Evaluate the security properties of hash functions, MACs, and digital signatures, including resistance to
collision and forgery
3 Apply cryptographic principles to design secure protocols and identify vulnerabilities in key exchange and
authentication mechanisms
4 WGU D334 Intro to Cryptography PA Questions and Correct Answers Plus Rationale
5 Already Graded A+
6 Latest 2026
7 2027 Update
8 Foundations of Cryptography
9 Applied Cryptography
10 Advanced Cryptography
11 Cryptography Review
ABSTRACT
Page 1
,This study document brings together 50 carefully worded exam questions drawn from WGU D334
Intro to Cryptography PA Questions and Correct Answers Plus Rationale (Already Graded A+)
Latest 2026-2027 Update, with the strongest emphasis placed on Analyze and compare symmetric
and asymmetric cryptographic algorithms and their appropriate use cases, Evaluate the security
properties of hash functions, MACs, and digital signatures, including resistance to collision and
forgery and Apply cryptographic principles to design secure protocols and identify vulnerabilities in
key exchange and authentication mechanisms. Every item follows the wording style and level of
reasoning you meet in the real paper, and each one is paired with a clear rationale so the correct
choice is never a guess. Work through the set at your own pace, mark the questions that slow you
down, then come back to them until the reasoning feels automatic. Learners who revise this way
walk into the exam room recognising the pattern behind the questions instead of meeting them for
the first time. Keep going - steady, honest practice is what turns a difficult paper into a comfortable
pass.
Q1 ANALYZE AND COMPARE SYMMETRIC AND ASYMMETRIC CRYPTOGRAPHIC
ALGORITHMS AND THEIR APPROPRIATE USE CASES
In a hybrid encryption scheme, a sender encrypts a random symmetric key K
using RSA-OAEP with the recipient's public key, then encrypts the message with
AES-256-GCM using K. Which property is primarily ensured by using RSA-OAEP
instead of textbook RSA for key encapsulation?
A. It prevents chosen-ciphertext attacks by making the encryption non-malleable. CORRECT
B. It reduces the computational cost of RSA encryption.
C. It ensures the confidentiality of the message without needing a symmetric cipher.
D. It allows the recipient to verify the sender's identity.
RATIONALE: RSA-OAEP adds randomness and a padding scheme that achieves IND-CCA2
security, thwarting chosen-ciphertext attacks and malleability. Textbook RSA is deterministic and
malleable. The other options misstate the purpose: OAEP does not reduce cost, replace
symmetric encryption, or provide authentication.
Page 2
, Q2 ANALYZE AND COMPARE SYMMETRIC AND ASYMMETRIC CRYPTOGRAPHIC
ALGORITHMS AND THEIR APPROPRIATE USE CASES
Consider a Merkle-Damgård hash function H with a 256-bit output. An attacker
finds two distinct messages M1 and M2 that produce the same hash. Which
security property is compromised?
A. Preimage resistance
B. Second preimage resistance
C. Collision resistance CORRECT
D. Pseudorandomness
RATIONALE: Collision resistance ensures it is infeasible to find any two distinct messages with
the same hash. Preimage resistance concerns finding a message given its hash; second
preimage resistance concerns finding a different message with the same hash as a given
message. Pseudorandomness is a property of the hash output distribution.
Q3 ANALYZE AND COMPARE SYMMETRIC AND ASYMMETRIC CRYPTOGRAPHIC
ALGORITHMS AND THEIR APPROPRIATE USE CASES
In a Diffie-Hellman key exchange over a prime modulus p, an attacker can solve
the Computational Diffie-Hellman (CDH) problem. What is the immediate
consequence for the protocol's security?
A. The attacker can compute the shared secret from the public values. CORRECT
B. The attacker can decrypt past sessions if long-term keys are compromised.
C. The attacker can impersonate the server without knowing its private key.
D. The attacker can forge digital signatures.
RATIONALE: CDH assumption states that given g^a and g^b, computing g^(ab) is hard. If CDH is
broken, the attacker can compute the shared secret directly. The other options describe different
attacks (forward secrecy, impersonation, signature forgery) not directly implied by breaking CDH.
Page 3
AND CORRECT ANSWERS PLUS RATIONALE
(ALREADY GRADED A+) LATEST 2026-2027 UPDATE
50 QUESTIONS
TABLE OF CONTENTS
# TOPIC
1 Analyze and compare symmetric and asymmetric cryptographic algorithms and their appropriate use
cases
2 Evaluate the security properties of hash functions, MACs, and digital signatures, including resistance to
collision and forgery
3 Apply cryptographic principles to design secure protocols and identify vulnerabilities in key exchange and
authentication mechanisms
4 WGU D334 Intro to Cryptography PA Questions and Correct Answers Plus Rationale
5 Already Graded A+
6 Latest 2026
7 2027 Update
8 Foundations of Cryptography
9 Applied Cryptography
10 Advanced Cryptography
11 Cryptography Review
ABSTRACT
Page 1
,This study document brings together 50 carefully worded exam questions drawn from WGU D334
Intro to Cryptography PA Questions and Correct Answers Plus Rationale (Already Graded A+)
Latest 2026-2027 Update, with the strongest emphasis placed on Analyze and compare symmetric
and asymmetric cryptographic algorithms and their appropriate use cases, Evaluate the security
properties of hash functions, MACs, and digital signatures, including resistance to collision and
forgery and Apply cryptographic principles to design secure protocols and identify vulnerabilities in
key exchange and authentication mechanisms. Every item follows the wording style and level of
reasoning you meet in the real paper, and each one is paired with a clear rationale so the correct
choice is never a guess. Work through the set at your own pace, mark the questions that slow you
down, then come back to them until the reasoning feels automatic. Learners who revise this way
walk into the exam room recognising the pattern behind the questions instead of meeting them for
the first time. Keep going - steady, honest practice is what turns a difficult paper into a comfortable
pass.
Q1 ANALYZE AND COMPARE SYMMETRIC AND ASYMMETRIC CRYPTOGRAPHIC
ALGORITHMS AND THEIR APPROPRIATE USE CASES
In a hybrid encryption scheme, a sender encrypts a random symmetric key K
using RSA-OAEP with the recipient's public key, then encrypts the message with
AES-256-GCM using K. Which property is primarily ensured by using RSA-OAEP
instead of textbook RSA for key encapsulation?
A. It prevents chosen-ciphertext attacks by making the encryption non-malleable. CORRECT
B. It reduces the computational cost of RSA encryption.
C. It ensures the confidentiality of the message without needing a symmetric cipher.
D. It allows the recipient to verify the sender's identity.
RATIONALE: RSA-OAEP adds randomness and a padding scheme that achieves IND-CCA2
security, thwarting chosen-ciphertext attacks and malleability. Textbook RSA is deterministic and
malleable. The other options misstate the purpose: OAEP does not reduce cost, replace
symmetric encryption, or provide authentication.
Page 2
, Q2 ANALYZE AND COMPARE SYMMETRIC AND ASYMMETRIC CRYPTOGRAPHIC
ALGORITHMS AND THEIR APPROPRIATE USE CASES
Consider a Merkle-Damgård hash function H with a 256-bit output. An attacker
finds two distinct messages M1 and M2 that produce the same hash. Which
security property is compromised?
A. Preimage resistance
B. Second preimage resistance
C. Collision resistance CORRECT
D. Pseudorandomness
RATIONALE: Collision resistance ensures it is infeasible to find any two distinct messages with
the same hash. Preimage resistance concerns finding a message given its hash; second
preimage resistance concerns finding a different message with the same hash as a given
message. Pseudorandomness is a property of the hash output distribution.
Q3 ANALYZE AND COMPARE SYMMETRIC AND ASYMMETRIC CRYPTOGRAPHIC
ALGORITHMS AND THEIR APPROPRIATE USE CASES
In a Diffie-Hellman key exchange over a prime modulus p, an attacker can solve
the Computational Diffie-Hellman (CDH) problem. What is the immediate
consequence for the protocol's security?
A. The attacker can compute the shared secret from the public values. CORRECT
B. The attacker can decrypt past sessions if long-term keys are compromised.
C. The attacker can impersonate the server without knowing its private key.
D. The attacker can forge digital signatures.
RATIONALE: CDH assumption states that given g^a and g^b, computing g^(ab) is hard. If CDH is
broken, the attacker can compute the shared secret directly. The other options describe different
attacks (forward secrecy, impersonation, signature forgery) not directly implied by breaking CDH.
Page 3
