Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

TEA cipher uses which of the following structure?

A. standard cipher structure
B. pseudo random structure
C. feistel structure
D. block structure
Answer» D. block structure
2.

For some number b, (1⁄b)⁻ⁿ is equal to _________

A. -bⁿ
B. nᵇ
C. bⁿ
D. none of the mentioned
Answer» D. none of the mentioned
3.

Radix complement can be obtained fromdiminished radix’s complement by _________

A. Adding one to diminished radox’s complement
B. Subtracting one to diminished radox’s complement
C. Both are same things
D. None of the mentioned
Answer» B. Subtracting one to diminished radox’s complement
4.

The ROT13 caesar cipher system has an offset of ___________

A. 13
B. 45
C. 71
D. 37
Answer» B. 45
5.

If there are 2⁵⁶ cipher texts per plain text and a total of 2¹⁸ plaintexts of length 18 exists. Then determine the number of distinct ciphertexts?

A. 761
B. 2⁷⁴
C. 186
D. 2⁸⁹
Answer» C. 186
6.

In which of the following systems, encryption slower than decryption?

A. elliptic curve cryptography
B. parabolic curve cryptography
C. symmetric cryptography
D. antisymmetric cryptography
Answer» C. symmetric cryptography
7.

How many bits of message does the Secure Hash Algorithm produce?

A. 160 bits
B. 1035 bits
C. 621 bits
D. 3761 bits
Answer» B. 1035 bits
8.

How many combinations of keys can be constructed from a 72 ciphertext stream cipher?

A. 4271
B. 7345
C. 3291
D. 2556
Answer» E.
9.

In a transposition cipher, the plaintext is constructed by the ________ of the ciphertext.

A. permutation
B. combination
C. sequence
D. series
Answer» B. combination
10.

In which cipher each letter of the plaintext is substituted by any other letter to form the cipher message?

A. Shift cipher
B. DES encryption
C. Block cipher
D. AES encryption
Answer» B. DES encryption
11.

Is 7, 8, 9, 11 are pairwise relatively prime.

A. True
B. False
C. May be True or False
D. Can't say
Answer» B. False
12.

There are 67 people in a company where they are using secret key encryption and decryption system for privacy purpose. Determine the number of secret keys required for this purpose?

A. 887
B. 6529
C. 2211
D. 834
Answer» D. 834
13.

One’s complement of a number x is y, then one’s complement of y is?

A. y
B. x
C. x + y
D. None of the mentioned
Answer» C. x + y
14.

If there is a unique prime number p₁ then a finite field F has the property of ______________

A. p₁x = 0 for all x in F
B. f(x) = f(xp₁) for all x in F
C. p₁ = y for all y in F
D. xy + p₁ for all x, y in F
Answer» B. f(x) = f(xp₁) for all x in F
15.

Which positive integer less than 21 are relatively prime to 21?

A. 18
B. 19
C. 21
D. 24
Answer» C. 21
16.

LCM(a, b) is equals to _________

A. ab/(GCD(a, b))
B. (a+b)/(GCD(a, b))
C. (GCD(a, b))/ab
D. none of the mentioned
Answer» B. (a+b)/(GCD(a, b))
17.

How many bits are there for random bits and error detection bits in the case of DES block ciphers?

A. 72, 1024
B. 56, 8
C. 104, 45
D. 32, 198
Answer» C. 104, 45
18.

The inverse of 3 modulo 7 is?

A. -1
B. -2
C. -3
D. -4
Answer» C. -3
19.

A multiplicative monoid defines the property of exponentiation with ________

A. integer exponents
B. fractional exponents
C. rational exponents
D. negative integer exponents
Answer» B. fractional exponents
20.

______ uses the concept of pseudo-random sequence.

A. Stream cipher
B. DES encryption
C. Caesar cipher
D. Block cipher
Answer» B. DES encryption
21.

If LCM of two number is 14 and GCD is 1 then the product of two numbers is?

A. 14
B. 15
C. 7
D. 49
Answer» B. 15
22.

The LCM of two number 1, b(integer) are _________

A. b + 2
B. 1
C. b
D. None of the mentioned
Answer» D. None of the mentioned
23.

If a, b are two distinct prime number than a highest common factor of a, b is ___________

A. 2
B. 0
C. 1
D. ab
Answer» D. ab
24.

Difference of two distinct prime numbers is?

A. Odd and prime
B. Even and composite
C. None of the mentioned
D. All of the mentioned
Answer» D. All of the mentioned
25.

If a, b, c, d are distinct prime numbers with an as smallest prime then a * b * c * d is a ___________

A. Odd number
B. Even number
C. Prime number
D. None of the mentioned
Answer» C. Prime number
26.

3 is the smallest prime number possible.

A. True
B. False
C. May be True or False
D. Can't say
Answer» C. May be True or False
27.

Sum of two different prime number is a ____________

A. Prime number
B. Composite number
C. Either Prime or Composite
D. None of the mentioned
Answer» D. None of the mentioned
28.

There are finite number of prime numbers.

A. True
B. False
C. May be True or False
D. Can't say
Answer» C. May be True or False
29.

How many prime numbers are there between 1 to 20?

A. 5
B. 6
C. 7
D. None of the mentioned
Answer» E.
30.

The number of factors of prime numbers are ___________

A. 2
B. 3
C. Depends on the prime number
D. None of the mentioned
Answer» B. 3
31.

What is the number ‘ 1’?

A. Prime number
B. Composite number
C. Neither Prime nor Composite
D. None of the mentioned
Answer» D. None of the mentioned
32.

All prime numbers are odd.

A. True
B. False
C. May be True or False
D. Can't say
Answer» C. May be True or False
33.

FIND_THE_SOLUTION_OF_X2‚ÄÖ√Ñ√∂‚ÀÖ¬¢¬¨‚ÀÛ_16_MOD_23?$#

A. x = 6 and 17
B. x = 4 and 19
C. x = 11 and 12
D. x = 7 and 16
Answer» C. x = 11 and 12
34.

Find the solution of x2≡ 2 mod 11 has a solution.$#

A. True
B. False
Answer» C.
35.

Find_the_solution_of_x^2≡3_mod_23$#

A. x≡±16 mod 23
B. x≡±13 mod 23
C. x≡±22 mod 23
D. x≡±7 mod 23
Answer» B. x‚Äö√Ñ√∂‚àö¬¢¬¨‚àû¬¨¬®¬¨¬±13 mod 23
36.

If we use exponentiation to encrypt/decrypt, the adversary can use logarithm to attack and this method is very efficient.

A. True
B. False
Answer» C.
37.

Find the solution of x2≡ 15 mod 23 has a solution?#

A. True
B. False
Answer» C.
38.

Euler’s Criterion can find the solution to x2 ≡ a (mod n).$

A. True
B. False
Answer» C.
39.

In Zp* with (p-1) elements exactly:

A. /2 elements are QR and
B. /2 elements are QNR.
C. True
D. False
Answer» B. /2 elements are QNR.
40.

Find the solution of x2≡ 3 mod 11$

A. x ≡ -9 mod 11 and x≡ 9 mod 11
B. x ≡ 9 mod 11
C. No Solution
D. x ≡ 5 mod 11 and x ≡ 6 mod 11
Answer» E.
41.

Equations have either no solution or exactly three incongruent solutions

A. True
B. False
Answer» C.