Unit 1: Computer Systems MCQs

Question 1

In a K-map, cells are ordered 00, 01, 11, 10 because:

Accepted Answer

neighbouring cells must differ in only one variable (Gray code)

Answer

it makes the map smaller

Answer

it is the binary counting order

Answer

it removes the need for groups

Question 2

Caesar cipher with key 3 encrypts "CAB" as:

Accepted Answer

FDE

Answer

DBC

Answer

ZXY

Answer

CAB3

Question 3

What does this Python code print? (bitwise operators on 0/1) python a, b, c = 1, 0, 1 print((a & b) c)

Accepted Answer

1

Answer

0

Answer

2

Answer

True

Question 4

How many links are needed for a full mesh of 5 computers?

Accepted Answer

10

Answer

5

Answer

20

Answer

25

Question 5

Which encryption is faster and better for encrypting large amounts of data?

Accepted Answer

Symmetric (e.g. AES)

Answer

Hashing

Answer

Asymmetric (e.g. RSA)

Answer

Caesar cipher

Question 6

The process of finding and removing errors from a program is called:

Accepted Answer

debugging

Answer

compiling

Answer

testing

Answer

deployment

Question 7

In which topology does each node connect to a central switch?

Accepted Answer

Star

Answer

Bus

Answer

Ring

Answer

Mesh

Question 8

Adding more servers to share the load is called:

Accepted Answer

horizontal scaling

Answer

vertical scaling

Answer

token passing

Answer

stress testing

Question 9

According to De Morgan's law, (A + B)' equals:

Accepted Answer

A'B'

Answer

(AB)'

Answer

AB

Answer

A' + B'

Question 10

In a bus topology, what is placed at both ends of the backbone?

Accepted Answer

Terminators

Answer

Routers

Answer

Tokens

Answer

Switches

Question 11

Checking whether a project is affordable compared with its benefits is called:

Accepted Answer

economic feasibility

Answer

technical feasibility

Answer

operational feasibility

Answer

schedule feasibility

Question 12

Flooding a website with traffic from thousands of infected computers is a:

Accepted Answer

DDoS attack

Answer

SQL backup

Answer

trojan

Answer

phishing attack

Question 13

Which test pushes a system beyond its expected load to find its breaking point?

Accepted Answer

Stress test

Answer

Acceptance test

Answer

Load test

Answer

Unit test

Question 14

A UML diagram that shows actors and what they can do with the system is a:

Accepted Answer

use-case diagram

Answer

flowchart

Answer

Gantt chart

Answer

class diagram

Question 15

Which gate gives output 1 only when all its inputs are 0?

Accepted Answer

NOR

Answer

AND

Answer

XOR

Answer

NAND

Question 16

Which model develops software in short sprints that each deliver working software?

Accepted Answer

Agile

Answer

Big-bang

Answer

V-model

Answer

Waterfall

Question 17

In which access method may a node send data only when it holds a special frame?

Accepted Answer

Token passing

Answer

Broadcasting

Answer

CSMA/CD

Answer

CSMA/CA

Question 18

Entering 100 for marks out of 100 is an example of which test data?

Accepted Answer

Boundary (extreme)

Answer

Normal

Answer

Random

Answer

Erroneous

Question 19

Wi-Fi networks use:

Accepted Answer

CSMA/CA

Answer

CSMA/CD

Answer

polling only

Answer

token passing

Question 20

The output of an XOR gate is 1 when:

Accepted Answer

the inputs are different

Answer

both inputs are 1

Answer

both inputs are 0

Answer

at least one input is 0

Question 21

Hardware or software that allows or blocks network traffic according to rules is a:

Accepted Answer

firewall

Answer

router only

Answer

hash

Answer

proxy

Question 22

The top node of a tree topology is called the:

Accepted Answer

root

Answer

client

Answer

terminator

Answer

leaf

Question 23

Unreadable data produced by encryption is called:

Accepted Answer

ciphertext

Answer

hash key

Answer

malware

Answer

plaintext

Question 24

A server is up 990 hours and down 10 hours. Its availability is:

Accepted Answer

99%

Answer

98%

Answer

99.9%

Answer

90%

Question 25

The main disadvantage of a star topology is:

Accepted Answer

the central switch is a single point of failure

Answer

it cannot use Ethernet

Answer

adding nodes is very difficult

Answer

one cable fault stops the whole network

Unit 1: Computer Systems MCQs — Computer Science (page 3)

51. In a K-map, cells are ordered 00, 01, 11, 10 because:

52. Caesar cipher with key 3 encrypts "CAB" as:

53. What does this Python code print? (bitwise operators on 0/1) python a, b, c = 1, 0, 1 print((a & b) c)

54. How many links are needed for a full mesh of 5 computers?

55. Which encryption is faster and better for encrypting large amounts of data?

56. The process of finding and removing errors from a program is called:

57. In which topology does each node connect to a central switch?

58. Adding more servers to share the load is called:

59. According to De Morgan's law, (A + B)' equals:

60. In a bus topology, what is placed at both ends of the backbone?

61. Checking whether a project is affordable compared with its benefits is called:

62. Flooding a website with traffic from thousands of infected computers is a:

63. Which test pushes a system beyond its expected load to find its breaking point?

64. A UML diagram that shows actors and what they can do with the system is a:

65. Which gate gives output 1 only when all its inputs are 0?

66. Which model develops software in short sprints that each deliver working software?

67. In which access method may a node send data only when it holds a special frame?

68. Entering 100 for marks out of 100 is an example of which test data?

69. Wi-Fi networks use:

70. The output of an XOR gate is 1 when:

71. Hardware or software that allows or blocks network traffic according to rules is a:

72. The top node of a tree topology is called the:

73. Unreadable data produced by encryption is called:

74. A server is up 990 hours and down 10 hours. Its availability is:

75. The main disadvantage of a star topology is:

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