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This section includes 141 Mcqs, each offering curated multiple-choice questions to sharpen your Cryptography and Network Security knowledge and support exam preparation. Choose a topic below to get started.
51. |
8 is quardratic residue of 11. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
52. |
What is the block size of blowfish block cipher? |
A. | 64 bits |
B. | 128 bits |
C. | 1043 bits |
D. | 10 bits |
Answer» B. 128 bits | |
53. |
Decimal equivalent of binary number 1010 is? |
A. | 11 |
B. | A |
C. | 10 |
D. | None of the mentioned |
Answer» D. None of the mentioned | |
54. |
The integer 2821 is a Carmichael number. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» B. False | |
55. |
Which of the number is not allowed in Binary representation of a number? |
A. | 0 |
B. | 1 |
C. | 2 |
D. | None of the mentioned |
Answer» D. None of the mentioned | |
56. |
The HCF of two prime numbers a and b is _________ |
A. | a⁄b |
B. | ab |
C. | a + b |
D. | 1 |
Answer» E. | |
57. |
If 0ᵃ is not equal to zero then which of the values a cannot take _________ |
A. | 1 |
B. | 2 |
C. | -1 |
D. | 0 |
Answer» E. | |
58. |
The solution of the linear congruence 4x = 5(mod 9) is? |
A. | 6(mod 9) |
B. | 8(mod 9) |
C. | 9(mod 9) |
D. | 10(mod 9) |
Answer» C. 9(mod 9) | |
59. |
The value of 5²⁰⁰³ mod 7 is? |
A. | 3 |
B. | 4 |
C. | 8 |
D. | 9 |
Answer» B. 4 | |
60. |
_______ is an example of asymmetric ciphers. |
A. | Block cipher |
B. | RSA encryption |
C. | AES encryption |
D. | Advanced cryptology |
Answer» C. AES encryption | |
61. |
Determine the value of x, where y = 7, e = 12 and n = 566 using modular exponentiation method (x ≡ yᵉ (mod n)). |
A. | 735 |
B. | 321 |
C. | 872 |
D. | 487 |
Answer» E. | |
62. |
LCM of 6, 10 is? |
A. | 60 |
B. | 30 |
C. | 10 |
D. | 6 |
Answer» C. 10 | |
63. |
If a, b are integers such that a > b then lcm(a, b) lies in _________ |
A. | a>lcm(a, b)>b |
B. | a>b>lcm(a, b) |
C. | lcm(a, b)>=a>b |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
64. |
The HCF of two number 1, b(integer) are _________ |
A. | b + 2 |
B. | 1 |
C. | b |
D. | None of the mentioned |
Answer» C. b | |
65. |
A Least Common Multiple of a, b is defined as __________ |
A. | It is the smallest integer divisible by both a and b |
B. | It is the greatest integer divisible by both a and b |
C. | It is the sum of the number a and b |
D. | None of the mentioned |
Answer» B. It is the greatest integer divisible by both a and b | |
66. |
Which of the following algorithms has better computational complexity than standard division algorithms? |
A. | Montgomery algorithm |
B. | Classical modular exponentiation algorithm |
C. | ASM algorithm |
D. | FSM algorithm |
Answer» C. ASM algorithm | |
67. |
The least common multiple of 41.42 and 42.41 is ____________ |
A. | 42 |
B. | 41 |
C. | 84 |
D. | 41.42 |
Answer» E. | |
68. |
9’s complement of 23456 is? |
A. | 87654 |
B. | 76543 |
C. | 12345 |
D. | none of the mentioned |
Answer» C. 12345 | |
69. |
Evaluate the expression 6359 mod 320. |
A. | 681 |
B. | 811 |
C. | 3781 |
D. | 279 |
Answer» E. | |
70. |
If a number is 2² x 3¹ x 5⁰ and b is 2² x 3¹ x 5¹ then hcf of a, b is? |
A. | 2² x 3¹ x 5¹ |
B. | 2² x 3² x 5² |
C. | 2¹ x 3¹ x 5⁰ |
D. | 2² x 3² x 5⁰ |
Answer» D. 2² x 3² x 5⁰ | |
71. |
Suppose that there are two primes, p₁ = 229 and p₂ = 61. Find the value of z and Φ. |
A. | 13969, 13680 |
B. | 5853, 23452 |
C. | 7793, 34565 |
D. | 17146, 69262 |
Answer» B. 5853, 23452 | |
72. |
_______ are used as the base of the Public Key Infrastructure. |
A. | SSL certificates |
B. | TLS certificates |
C. | X.509 certificates |
D. | HAS certificates |
Answer» D. HAS certificates | |
73. |
________ can decrypt traffic to make it available to all other network security functions such as web proxies. |
A. | SSL visibility appliances |
B. | RSA appliances |
C. | Rodriguez cipher system |
D. | Standard cipher system |
Answer» B. RSA appliances | |
74. |
If ab = 1, where a and b are real numbers then? |
A. | a = b⁻¹ |
B. | b = a |
C. | a = b = 2 |
D. | none of the mentioned |
Answer» B. b = a | |
75. |
The linear combination of gcd(252, 198) = 18 is? |
A. | 252*4 – 198*5 |
B. | 252*5 – 198*4 |
C. | 252*5 – 198*2 |
D. | 252*4 – 198*4 |
Answer» B. 252*5 – 198*4 | |
76. |
What are the steps in the Feistel function? |
A. | expansion, mixing, substitution, permutation |
B. | extract, transform, load |
C. | extract, load, transform |
D. | expansion, divide, mixing, permutation |
Answer» B. extract, transform, load | |
77. |
Which of the following methods uses the concept that exponentiation is computationally inexpensive in the finite field? |
A. | Diffie-HEllman key exchange |
B. | RSA key exchange |
C. | Arithmetic key exchange |
D. | FSM method |
Answer» B. RSA key exchange | |
78. |
Suppose in order to get a message across enemy lines, we need to choose an initial secret key say, 100110. What will be the decrypted cipher when the original message is 010010011. |
A. | 110100 |
B. | 1001011 |
C. | 0011010 |
D. | 011011 |
Answer» B. 1001011 | |
79. |
In cryptography system, the value of z in x ≡ zᵉ (mod m) should be at least ______ |
A. | 1024 bits |
B. | 1GB |
C. | 596 bits |
D. | 54 Bytes |
Answer» B. 1GB | |
80. |
The greatest common divisor of 0 and 5 is ___________ |
A. | 0 |
B. | 1 |
C. | 2 |
D. | 5 |
Answer» C. 2 | |
81. |
According to congruence relation, find the remainder of 56 mod 24. |
A. | 10 |
B. | 12 |
C. | 6 |
D. | 4 |
Answer» D. 4 | |
82. |
If a is a real number, then a⁰ is defined as _________ |
A. | 0 |
B. | a |
C. | 1 |
D. | -1 |
Answer» B. a | |
83. |
The linear combination of gcd(117, 213) = 3 can be written as _________ |
A. | 11*213 + (-20)*117 |
B. | 10*213 + (-20)*117 |
C. | 11*117 + (-20)*213 |
D. | 20*213 + (-25)*117 |
Answer» B. 10*213 + (-20)*117 | |
84. |
Using RSA algorithm what is the value of cipher test c if the plain text e = 7 and P = 5, q = 16 & n = 832. Determine the Euler’s totient function for the plain text? |
A. | 47 |
B. | 584 |
C. | 428 |
D. | 60 |
Answer» E. | |
85. |
4 is quardratic residue of 7. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» B. False | |
86. |
In encryption, which of the following is the best text encoding technique? |
A. | ASCII encoding |
B. | Hex-encoding |
C. | Unicode technique |
D. | Base64 encoding |
Answer» D. Base64 encoding | |
87. |
Octal number may contain digits from 1 to 8. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
88. |
The product of two numbers are 12 and there LCM is 6 then HCF is? |
A. | 12 |
B. | 2 |
C. | 6 |
D. | None of the mentioned |
Answer» C. 6 | |
89. |
Let A’s public key is n=6, 736, 180, 7817, 961, 456, 267 and e = 5 and B sends the ciphertext. c = 456, 871, 122, 391, 882, 538 to A. Determine B’s message in numeric format? |
A. | 235813 |
B. | 57971.89 |
C. | 770190.04 |
D. | 687651.9 |
Answer» D. 687651.9 | |
90. |
F in hexadecimal representation is equivalent to 9 in decimal. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
91. |
The Fermat’s little theorem for odd prime p and coprime number a is? |
A. | aᵖ⁻¹ ≡ 1 (mod p) |
B. | aᵖ⁻¹ ≡ 7 (mod p) |
C. | aᵖ⁽²⁾⁻¹ ≡ 1 (mod p) |
D. | none of the mentioned |
Answer» B. aᵖ⁻¹ ≡ 7 (mod p) | |
92. |
HCF of 6, 10 is? |
A. | 60 |
B. | 30 |
C. | 10 |
D. | 2 |
Answer» E. | |
93. |
If there exist an integer x such that x² ≡ q (mod n). then q is called ______________ |
A. | Quadratic Residue |
B. | Linear Residue |
C. | Pseudoprime |
D. | None of the mentioned |
Answer» B. Linear Residue | |
94. |
The inverse of 7 modulo 26 is? |
A. | 12 |
B. | 14 |
C. | 15 |
D. | 20 |
Answer» D. 20 | |
95. |
There is no secret key in case of ____________ |
A. | Symmetric ciphers |
B. | Asymmetric ciphers |
C. | RSA encryption |
D. | Alpha-numeric cryptography |
Answer» B. Asymmetric ciphers | |
96. |
The greatest common divisor of 3¹³.5¹⁷ and 2¹².3⁵ is __________ |
A. | 3⁰ |
B. | 3¹ |
C. | 3³ |
D. | 3⁵ |
Answer» E. | |
97. |
The linear combination of gcd(10, 11) = 1 can be written as _________ |
A. | (-1)*10 + 1*11 |
B. | (-2)*10 + 2*11 |
C. | 1*10 + (-1)*11 |
D. | (-1)*10 + 2*11 |
Answer» B. (-2)*10 + 2*11 | |
98. |
A Highest Common Factor of a, b is defined as ___________ |
A. | It is the smallest integer divisible by both a and b |
B. | It is the greatest integer divisor of both a and b |
C. | It is the sum of the number a and b |
D. | None of the mentioned |
Answer» C. It is the sum of the number a and b | |
99. |
Pseudo prime are classified based on property which they satisfy, which of the following are classes of pseudoprimes? |
A. | Fermat pseudoprime |
B. | Fibonacci pseudoprime |
C. | Euler pseudoprime |
D. | All of the mentioned |
Answer» E. | |
100. |
What is the one’s complement of the number 1010110? |
A. | 1111111 |
B. | 0101001 |
C. | 1100110 |
D. | None of the mentioned |
Answer» C. 1100110 | |