Pakistan Railways Clerk / Assistant (BS-11): Computer Science MCQs with Answers

Question 1

How many bytes are in 1 Megabyte (MB)?

Accepted Answer

1048576

Answer

1024

Answer

1000000

Answer

524288

Question 2

A 32-bit processor can directly address a maximum of how much RAM?

Accepted Answer

4 GB

Answer

2 GB

Answer

8 GB

Answer

16 GB

Question 3

What type of memory is used to store the BIOS firmware?

Accepted Answer

ROM

Answer

DRAM

Answer

SRAM

Answer

Virtual Memory

Question 4

Virtual memory is an extension of which physical component?

Accepted Answer

RAM

Answer

Cache Memory

Answer

Hard Disk

Answer

CPU Registers

Question 5

Which of the following is the correct order of memory speed from fastest to slowest?

Accepted Answer

Registers > Cache > RAM > HDD

Answer

RAM > Cache > Registers > HDD

Answer

Cache > RAM > Registers > HDD

Answer

HDD > RAM > Cache > Registers

Question 6

Which protocol is used for file transfers between computers?

Accepted Answer

FTP

Answer

SMTP

Answer

HTTP

Answer

DNS

Question 7

What is the octal equivalent of binary 110101?

Accepted Answer

63

Answer

65

Answer

55

Answer

75

Question 8

Which protocol is used to retrieve emails from a mail server while keeping them on the server?

Accepted Answer

IMAP

Answer

SMTP

Answer

POP3

Answer

FTP

Question 9

Which OSI layer is responsible for framing and MAC addressing?

Accepted Answer

Data Link Layer

Answer

Physical Layer

Answer

Network Layer

Answer

Transport Layer

Question 10

In a bus topology, if the main cable (backbone) fails, what happens?

Accepted Answer

The entire network fails

Answer

Only one node fails

Answer

The network slows down

Answer

Other nodes reroute traffic

Question 11

What memory management technique divides memory into fixed-size blocks called frames?

Accepted Answer

Paging

Answer

Segmentation

Answer

Swapping

Answer

Compaction

Question 12

In Priority Scheduling, which problem occurs when low-priority processes never get CPU time?

Accepted Answer

Starvation

Answer

Thrashing

Answer

Convoy Effect

Answer

Deadlock

Question 13

Which memory management technique divides a program into variable-sized logical units?

Accepted Answer

Segmentation

Answer

Paging

Answer

Fragmentation

Answer

Swapping

Question 14

Which layer of the TCP/IP model handles logical addressing and routing?

Accepted Answer

Internet Layer

Answer

Network Access Layer

Answer

Application Layer

Answer

Transport Layer

Question 15

In IEEE 754 single-precision floating point, how many bits are used for the exponent field?

Accepted Answer

8

Answer

23

Answer

1

Answer

32