WGU C839 - Introduction to Cryptography Newest 2024- 2025 Complete
300 Frequently Tested Questions with Correct Verified Answers
1. What type of encryption uses different keys to en- D
crypt and decrypt the message?
A Symmetric
B Private key
C Secure
D Asymmetric
2. The most widely used asymmetric encryption algo- A
rithm is what?
A RSA
B Vigenere
C DES
D Caesar Cipher
3. Original, unencrypted information is referred to as B
____.
A text
B plaintext
C cleantext
D ciphertext
4. Which of the following is NOT an asymmetric sys- D
tem?
A PGP
B RSA
C SSL
D DES
5. In order for User A to send User B an encrypted mes- C
sage that only User B can read, User A must encrypt
message with which of the following keys?
A User A's public key
B User A's private key
, WGU C839 - Intro to Cryptography Newest 2024 -2025
C User B's public key
D User B's private key
6. The greatest weakness with symmetric algorithms is B
_____.
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
7. Which of the following is generally true about block D
sizes?
A Smaller block sizes increase security
B Block sizes must be more than 256 bits to be secure
C Block size is irrelevant to security
D Larger block sizes increase security
8. A _____ is a function that takes a variable-size input B
m and returns a fixed-size string.
A Symmetric cipher
B Hash
C Asymmetric cipher
D Feistel
9. Which of the following is a cryptographic protocol D
that allows two parties to establish a shared key over
an insecure channel?
A Elliptic Curve
B RSA
C MD5
D Diffie-Hellman
10. A _________ is a digital representation of information A
that identifies you as a relevant entity by a trusted
third party?
, WGU C839 - Intro to Cryptography NEWEST 2024 -2025
A Digital Signature
B Hash
C Ownership stamp
D Digest
11. What is the standard used by most digital certifi- A
cates?
A X.509
B CRL
C RFC 2298
D OCSP
12. DES uses keys of what size? A
A 56 bits
B 192 bits
C 128 bits
D 64 bits
13. Which of the following is NOT a key size used by A
AES?
A 512 bits
B 128 bits
C 192 bits
D 256 bits
14. Which of the following was a multi alphabet cipher A
widely used from the 16th century (1553) to the early
20th century (1900s)?
A Vigenere
B Caesar
C Atbash
D Scytale
15. Which of the following is a substitution cipher used D
by ancient Hebrew scholars?
, WGU C839 - Intro to Cryptography Newest 2024 -2025
A Caesar
B Vigenere
C Scytale
D Atbash
16. Shifting each letter in the alphabet a fixed number of D
spaces to the right or left is an example of what?
A Bit shifting
B Confusion
C Multi substitution
D Single substitution
17. Which of the following most accurately defines en- A
cryption?
A changing a message so it can only be easily read
by the intended recipient
B Making binary changes to a message to conceal it
C changing a message using complex mathematics
D Applying keys to plain text
18. If you use substitution alone, what weakness is pre- D
sent in the resulting cipher text?
A It is the same length as the original text
B It is easily broken with modern computers.
C It is too simple.
D Because it maintains letter and word frequency.
19. _____ uses at least two different shifts, changing the B
shift with different letters in the plain text.
A Atbash
B multi-alphabet encryption
C Scytale
D Caesar cipher
300 Frequently Tested Questions with Correct Verified Answers
1. What type of encryption uses different keys to en- D
crypt and decrypt the message?
A Symmetric
B Private key
C Secure
D Asymmetric
2. The most widely used asymmetric encryption algo- A
rithm is what?
A RSA
B Vigenere
C DES
D Caesar Cipher
3. Original, unencrypted information is referred to as B
____.
A text
B plaintext
C cleantext
D ciphertext
4. Which of the following is NOT an asymmetric sys- D
tem?
A PGP
B RSA
C SSL
D DES
5. In order for User A to send User B an encrypted mes- C
sage that only User B can read, User A must encrypt
message with which of the following keys?
A User A's public key
B User A's private key
, WGU C839 - Intro to Cryptography Newest 2024 -2025
C User B's public key
D User B's private key
6. The greatest weakness with symmetric algorithms is B
_____.
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
7. Which of the following is generally true about block D
sizes?
A Smaller block sizes increase security
B Block sizes must be more than 256 bits to be secure
C Block size is irrelevant to security
D Larger block sizes increase security
8. A _____ is a function that takes a variable-size input B
m and returns a fixed-size string.
A Symmetric cipher
B Hash
C Asymmetric cipher
D Feistel
9. Which of the following is a cryptographic protocol D
that allows two parties to establish a shared key over
an insecure channel?
A Elliptic Curve
B RSA
C MD5
D Diffie-Hellman
10. A _________ is a digital representation of information A
that identifies you as a relevant entity by a trusted
third party?
, WGU C839 - Intro to Cryptography NEWEST 2024 -2025
A Digital Signature
B Hash
C Ownership stamp
D Digest
11. What is the standard used by most digital certifi- A
cates?
A X.509
B CRL
C RFC 2298
D OCSP
12. DES uses keys of what size? A
A 56 bits
B 192 bits
C 128 bits
D 64 bits
13. Which of the following is NOT a key size used by A
AES?
A 512 bits
B 128 bits
C 192 bits
D 256 bits
14. Which of the following was a multi alphabet cipher A
widely used from the 16th century (1553) to the early
20th century (1900s)?
A Vigenere
B Caesar
C Atbash
D Scytale
15. Which of the following is a substitution cipher used D
by ancient Hebrew scholars?
, WGU C839 - Intro to Cryptography Newest 2024 -2025
A Caesar
B Vigenere
C Scytale
D Atbash
16. Shifting each letter in the alphabet a fixed number of D
spaces to the right or left is an example of what?
A Bit shifting
B Confusion
C Multi substitution
D Single substitution
17. Which of the following most accurately defines en- A
cryption?
A changing a message so it can only be easily read
by the intended recipient
B Making binary changes to a message to conceal it
C changing a message using complex mathematics
D Applying keys to plain text
18. If you use substitution alone, what weakness is pre- D
sent in the resulting cipher text?
A It is the same length as the original text
B It is easily broken with modern computers.
C It is too simple.
D Because it maintains letter and word frequency.
19. _____ uses at least two different shifts, changing the B
shift with different letters in the plain text.
A Atbash
B multi-alphabet encryption
C Scytale
D Caesar cipher
