CRYPTOGRAPHY QUESTIONS AND CORRECT
ANSWERS PLUS RATIONALE LATEST UPDATE
50 QUESTIONS
TABLE OF CONTENTS
# TOPIC
1 Analyze security properties of cryptographic algorithms and identify appropriate use cases
2 Evaluate vulnerabilities in cryptographic protocols and recommend mitigations
3 Apply principles of key management, digital signatures, and PKI to design secure systems
4 WGU D334 V1 Pre
5 Assessment Intro to Cryptography Questions and Correct Answers Plus Rationale Latest Update
6 Foundations of Cryptography and Information Assurance
7 Applied Cryptography and Information Assurance
8 Advanced Cryptography and Information Assurance
9 Cryptography and Information Assurance Review
ABSTRACT
This study document brings together 50 carefully worded exam questions drawn from WGU D334
V1 Pre-Assessment Intro to Cryptography Questions and Correct Answers Plus Rationale Latest
Update, with the strongest emphasis placed on Analyze security properties of cryptographic
algorithms and identify appropriate use cases, Evaluate vulnerabilities in cryptographic protocols
and recommend mitigations, Apply principles of key management, digital signatures and and PKI
to design secure systems. 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.
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,Q1 ANALYZE SECURITY PROPERTIES OF CRYPTOGRAPHIC ALGORITHMS AND IDENTIFY
APPROPRIATE USE CASES
A developer must encrypt a 10 GB database backup for long-term archival. Which
AES mode provides authenticated encryption and is recommended by NIST for
this purpose?
A. AES-CBC with HMAC-SHA256
B. AES-GCM CORRECT
C. AES-ECB
D. AES-CTR
RATIONALE: AES-GCM is an authenticated encryption mode providing confidentiality and
integrity in one pass, and is NIST-approved for high-volume data. CBC with HMAC is secure but
requires two keys and separate MAC, while ECB and CTR lack authentication.
Q2 ANALYZE SECURITY PROPERTIES OF CRYPTOGRAPHIC ALGORITHMS AND IDENTIFY
APPROPRIATE USE CASES
In a Diffie-Hellman key exchange over an unauthenticated channel, an attacker
intercepts and replaces public keys. Which security property is directly
compromised?
A. Confidentiality of the shared secret
B. Integrity of the exchanged messages
C. Authentication of the parties CORRECT
D. Forward secrecy of session keys
RATIONALE: Without authentication, DH is vulnerable to man-in-the-middle, where the attacker
impersonates each party. Confidentiality of the shared secret is still achieved between attacker
and each party, but the parties are not authenticated to each other.
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, Q3 ANALYZE SECURITY PROPERTIES OF CRYPTOGRAPHIC ALGORITHMS AND IDENTIFY
APPROPRIATE USE CASES
A security team must store user passwords for authentication. Which approach
best mitigates offline brute-force attacks if the password database is stolen?
A. SHA-256 hashing with a unique salt per user
B. AES-256 encryption of passwords with a secret key
C. Argon2id with a unique salt and tuned memory/iterations CORRECT
D. MD5 hashing with a global salt
RATIONALE: Argon2id is a memory-hard, slow hashing function designed to resist GPU/ASIC
brute-force, and is current best practice (e.g., OWASP). SHA-256 is fast and vulnerable to
brute-force; AES encryption requires key management and is reversible; MD5 is
cryptographically broken.
Q4 ANALYZE SECURITY PROPERTIES OF CRYPTOGRAPHIC ALGORITHMS AND IDENTIFY
APPROPRIATE USE CASES
A digital signature scheme must provide non-repudiation and integrity. Which key
is used to generate the signature, and which to verify it?
A. Sign with sender's private key; verify with sender's public key CORRECT
B. Sign with sender's public key; verify with sender's private key
C. Sign with a shared secret key; verify with the same key
D. Sign with recipient's public key; verify with recipient's private key
RATIONALE: Digital signatures use the sender's private key to sign and the corresponding public
key to verify, ensuring only the private key holder could have signed. This provides
non-repudiation and integrity. Shared-key signatures (HMAC) do not provide non-repudiation.
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