250+ TOP MCQs on Atbash Cipher and Answers

Data Structures & Algorithms Multiple Choice Questions on “Atbash Cipher”.

1. Which of the following cipher does not require a key for encrypting plain text?
a) atbash cipher
b) affine cipher
c) playfair cipher
d) vigenere cipher

Answer: a
Clarification: Out of the given options only atbash cipher does not require a key for encryption. Atbash cipher is an example of a substitution cipher.

2. Atbash cipher was originally used for encrypting _____________
a) english alphabet
b) greek alphabet
c) hebrew alphabet
d) hindi alphabet

Answer: c
Clarification: Atbash cipher was originally built to encrypt hebrew alphabet. But it can be used to encrypt any type of alphabets.

3. Which of the following cipher is a special case of affine cipher?
a) Vigenere cipher
b) Autokey cipher
c) Atbash cipher
d) Hill cipher
Answer: c
Clarification: Atbash cipher is a special case of affine cipher. We have to assume a=b=25 as the key in affine cipher to get the same encryption.

4. Choose the weakest cipher from the following?
a) vigenere cipher
b) rail fence cipher
c) hill cipher
d) atbash cipher
Answer: d
Clarification: Atbash cipher is the weakest cipher out of the given options. This is because it is a simple mono alphabetic substitution cipher with almost no security. It can be cracked without even knowing which technique has been used for encryption.

5. Which of the following is a mono alphabetic substitution cipher?
a) vigenere cipher
b) one time pad cipher
c) play fair cipher
d) atbash cipher

Answer: d
Clarification: Atbash cipher is the only mono alphabetic substitution cipher out of the given options. All the remaining options fall under the category of poly alphabetic cipher.

6. Atbash cipher is less secure than affine cipher.
a) True
b) False

Answer: a
Clarification: Affine cipher is more secure as compared to pigpen cipher. Atbash cipher is a special case of affine cipher and can be cracked without even knowing which technique has been used for encryption.

7. Atbash cipher is an example of?
a) Mono alphabetic substitution cipher
b) Transposition cipher
c) Poly alphabetic substitution cipher
d) Geometric substitution cipher

A - Z	  J - Q	    S - H
B - Y	  K - P	    T - G
C - X	  L - O	    U - F
D - W	  M - N	    V - E
E - V	  N - M	    W - D
F - U	  O - L	    X - C
G - T	  P - K	    Y - B
H - S	  Q - J	    Z - A
I - R	  R - I

8. Atbash cipher cannot be cracked until the exact type of encryption of ciphered text is known.
a) True
b) False

Answer: b
Clarification: Atbash cipher is a very weak cipher. It can be easily broken without even knowing the exact technique which has been used for encryption. We can just assume the ciphered text to be a substitution cipher in order to crack it.

9. What will be the ciphered text corresponding to plain text “SECRET” if atbash cipher is used for encryption?
a) VHIXVG
b) HVXIVG
c) HXVIVG
d) VIHXIV

A - Z	  J - Q	    S - H
B - Y	  K - P	    T - G
C - X	  L - O	    U - F
D - W	  M - N	    V - E
E - V	  N - M	    W - D
F - U	  O - L	    X - C
G - T	  P - K	    Y - B
H - S	  Q - J	    Z - A
I - R	  R - I

10. What will be the plain text corresponding to ciphered text “MAO” if atbash cipher is used for encryption?
a) NZL
b) IND
c) AUS
d) ENG

A - Z	  J - Q	    S - H
B - Y	  K - P	    T - G
C - X	  L - O	    U - F
D - W	  M - N	    V - E
E - V	  N - M	    W - D
F - U	  O - L	    X - C
G - T	  P - K	    Y - B
H - S	  Q - J	    Z - A
I - R     R - I

11. Which of the following is not true about atbash cipher?
a) it is a mono alphabetic substitution cipher
b) it can only be used to encrypt hebrew alphabet
c) it is a special case of affine cipher
d) it is weaker than playfair cipher

Answer: b
Clarification: Atbash cipher was originally built to encrypt hebrew alphabet. But it can be used to encrypt any type of alphabets.