PGT Computer Science (Level-3), (HTET Practice MCQs) (Part-II)

Total Questions: 100

41. In _____________ substitution, a character in the plaintext is always changed to the same character in the ciphertext, regardless of its position in the text.

Correct Answer: B. monoalphabetic

42. In classful addressing, the IP address 190.255.254.254 belongs to

Correct Answer: B. Class B

43. In hierarchical routing with 4800 routers, what region and cluster sizes should be chosen to minimize the size of the routing table for a three-layer hierarchy?

Correct Answer: D. 15 clusters, 16 regions and 20 routers

44. In IPV₄ header, the ___________ field is needed to allow the destination host to determine which datagram a newly arrived fragments belongs to

Correct Answer: A. identification

45. Given L1 = L (a*baa*) and L2 = L(ab*). The regular expression corresponding to language 1.3 = LI/L2 (right quotient) is given by

Correct Answer: C. a*ba*

46. Given the production rules of a grammar G1 as

S₁ → AB | aaB
A → a  | Aa
B → b
and the production rules of a grammar G2 as
S₂ → aS₂bS₂ | bS₂aS₂ | λ
Which of the following is correct statement?

Correct Answer: B. G1 is ambiguous and G2 is ambiguous.

47. Given a grammar:

S1 → Sc, S → SA | A, A → aSb | ab,
there is a rightmost derivation S1 ⇒ Sc ⇒ SAC
SaSbc
Thus, SaSbc is a right sentential form, and its handle is

Correct Answer: D. aSb

48. The equivalent production rules corresponding to the production rules

Correct Answer: D.

49. Given a Non-deterministic Finite Automation (NFA) with states p and r as initial and final states respectively and transition table as given below:


The minimum number of states required in
Deterministic Finite Automation (DFA) equivalent to NFA is

Correct Answer: C. 3

50. Which is the correct statement(s) for Non-Recursive predictive parser?

Correct Answer: D. Both statements S1 and S2 are correct