Cryptography and System Security Practice
Questions with Detailed Rationales latest 2026
Latest version Q&A |INSTANT DOWNLOAD
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1. Which of the following is a symmetric encryption
algorithm?
A. RSA
B. AES
C. ECC
D. DSA
Rationale: AES (Advanced Encryption Standard) uses the same
key for encryption and decryption, making it a symmetric
algorithm.
2. What is the main purpose of a cryptographic hash function?
A. Encrypt messages
B. Ensure data integrity
C. Generate keys
D. Authenticate users
Rationale: Hash functions produce a fixed-size output from
input data to verify that data hasn’t been altered.
3. Which attack involves intercepting and altering
communication between two parties?
A. Phishing
B. Man-in-the-Middle (MITM)
C. Brute-force
,D. Denial-of-Service (DoS)
Rationale: MITM attacks intercept communication and can
modify messages without the users knowing.
4. In public key infrastructure (PKI), which key is used for
encryption?
A. Symmetric key
B. Recipient’s public key
C. Sender’s private key
D. Session key
Rationale: The public key of the recipient is used to encrypt
messages, which only their private key can decrypt.
5. What does SSL/TLS primarily provide?
A. Antivirus protection
B. Secure communication over networks
C. Firewall functionality
D. User authentication only
Rationale: SSL/TLS ensures encryption and integrity for data
transmitted over networks.
6. Which of these is a block cipher mode of operation?
A. RSA
B. CBC (Cipher Block Chaining)
C. Diffie-Hellman
D. SHA-256
Rationale: CBC is a block cipher mode that chains blocks to
improve encryption security.
,7. What is the main advantage of asymmetric cryptography
over symmetric cryptography?
A. Faster encryption
B. Secure key exchange without prior sharing
C. Lower computational cost
D. Uses shorter keys
Rationale: Asymmetric encryption allows secure
communication without needing a shared secret key
beforehand.
8. Which of the following is a type of malware designed to
monitor user activity?
A. Trojan
B. Spyware
C. Worm
D. Adware
Rationale: Spyware collects data from a user’s device without
consent.
9. Which protocol is commonly used to securely transfer files
over the internet?
A. FTP
B. Telnet
C. SFTP
D. HTTP
Rationale: SFTP encrypts both commands and data for secure
file transfer.
, 10. Which of the following is an example of two-factor
authentication?
A. Password only
B. Security questions only
C. Password + Fingerprint
D. PIN only
Rationale: Two-factor authentication requires two different
verification methods: something you know + something you
have or are.
11. What is the primary goal of a firewall?
A. Encrypt files
B. Control incoming and outgoing network traffic
C. Detect malware
D. Perform backups
Rationale: Firewalls enforce rules that allow or block network
traffic based on security policies.
12. Which type of attack relies on repeatedly trying all
possible keys?
A. MITM
B. Phishing
C. Brute-force
D. SQL Injection
Rationale: Brute-force attacks systematically try every possible
key or password combination.
13. What is the main characteristic of a one-way hash
function?
Questions with Detailed Rationales latest 2026
Latest version Q&A |INSTANT DOWNLOAD
1. Which of the following is a symmetric encryption
algorithm?
A. RSA
B. AES
C. ECC
D. DSA
Rationale: AES (Advanced Encryption Standard) uses the same
key for encryption and decryption, making it a symmetric
algorithm.
2. What is the main purpose of a cryptographic hash function?
A. Encrypt messages
B. Ensure data integrity
C. Generate keys
D. Authenticate users
Rationale: Hash functions produce a fixed-size output from
input data to verify that data hasn’t been altered.
3. Which attack involves intercepting and altering
communication between two parties?
A. Phishing
B. Man-in-the-Middle (MITM)
C. Brute-force
,D. Denial-of-Service (DoS)
Rationale: MITM attacks intercept communication and can
modify messages without the users knowing.
4. In public key infrastructure (PKI), which key is used for
encryption?
A. Symmetric key
B. Recipient’s public key
C. Sender’s private key
D. Session key
Rationale: The public key of the recipient is used to encrypt
messages, which only their private key can decrypt.
5. What does SSL/TLS primarily provide?
A. Antivirus protection
B. Secure communication over networks
C. Firewall functionality
D. User authentication only
Rationale: SSL/TLS ensures encryption and integrity for data
transmitted over networks.
6. Which of these is a block cipher mode of operation?
A. RSA
B. CBC (Cipher Block Chaining)
C. Diffie-Hellman
D. SHA-256
Rationale: CBC is a block cipher mode that chains blocks to
improve encryption security.
,7. What is the main advantage of asymmetric cryptography
over symmetric cryptography?
A. Faster encryption
B. Secure key exchange without prior sharing
C. Lower computational cost
D. Uses shorter keys
Rationale: Asymmetric encryption allows secure
communication without needing a shared secret key
beforehand.
8. Which of the following is a type of malware designed to
monitor user activity?
A. Trojan
B. Spyware
C. Worm
D. Adware
Rationale: Spyware collects data from a user’s device without
consent.
9. Which protocol is commonly used to securely transfer files
over the internet?
A. FTP
B. Telnet
C. SFTP
D. HTTP
Rationale: SFTP encrypts both commands and data for secure
file transfer.
, 10. Which of the following is an example of two-factor
authentication?
A. Password only
B. Security questions only
C. Password + Fingerprint
D. PIN only
Rationale: Two-factor authentication requires two different
verification methods: something you know + something you
have or are.
11. What is the primary goal of a firewall?
A. Encrypt files
B. Control incoming and outgoing network traffic
C. Detect malware
D. Perform backups
Rationale: Firewalls enforce rules that allow or block network
traffic based on security policies.
12. Which type of attack relies on repeatedly trying all
possible keys?
A. MITM
B. Phishing
C. Brute-force
D. SQL Injection
Rationale: Brute-force attacks systematically try every possible
key or password combination.
13. What is the main characteristic of a one-way hash
function?
