I85PREP
⌘ K
Assam ASSEB HSLC Elective Computer Science study materials
Assam ASSEB HSLC Elective Computer Science study resources

Assam ASSEB HSLC Elective Computer Science practice questions

One question at a time. Build your Assam ASSEB HSLC Elective Computer Science understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Computer Fundamentals and Number Systems

In the ASSEB HSLC Computer Science syllabus, which of the following is classified as an input device?

  1. Monochrome monitor
  2. Dot-matrix printer
  3. Optical character reader Correct answer.
  4. Plotter

Explanation

An input device sends data from the outside world into the computer for processing. An optical character reader scans printed characters and converts them into machine-readable codes, so it is an input device. Plotters, monitors and printers all deliver results outward and are therefore output devices.

Question 2Computer Fundamentals and Number Systems

A computer executes instructions stored in its main memory one after another in a fixed sequence. Which fundamental characteristic of a computer does this describe?

  1. Diligence
  2. Storage capacity
  3. Versatility
  4. Automatic functioning Correct answer.

Explanation

Once a program is loaded, the computer carries out the stored instructions in sequence without a human guiding each step; this ability is called automatic functioning. Diligence refers to working long hours without fatigue, versatility to handling many kinds of tasks, and storage capacity to holding large amounts of data. Only the stored-program sequence is the defining feature of automatic operation.

Question 3Computer Fundamentals and Number Systems

Which generation of computers is associated with the use of integrated circuits as the main switching component?

  1. Third generation Correct answer.
  2. Second generation
  3. First generation
  4. Fourth generation

Explanation

The third generation of computers replaced individual transistors with integrated circuits, in which many components are fabricated on a single silicon chip. First-generation machines used vacuum tubes, the second used discrete transistors, and the fourth used microprocessors (VLSI). Hence integrated circuits define the third generation.

Question 4Computer Fundamentals and Number Systems

What is the decimal value of the binary number 1101?

  1. 14
  2. 15
  3. 11
  4. 13 Correct answer.

Explanation

Each binary digit is multiplied by the corresponding power of two: 1×8 + 1×4 + 0×2 + 1×1. Adding these place values gives 8 + 4 + 0 + 1 = 13. Therefore 1101 in binary equals thirteen in decimal.

Question 5Computer Fundamentals and Number Systems

Which unit is the smallest addressable storage location in a computer's main memory?

  1. Word
  2. Byte Correct answer.
  3. Nibble
  4. Bit

Explanation

A byte, normally eight bits, is the smallest unit that can be given a unique address in main memory. A bit is smaller but is not individually addressable, a nibble is half a byte, and a word is a larger processing unit whose size depends on the machine. Thus the byte is the standard addressable unit.

Question 6Computer Fundamentals and Number Systems

One kilobyte in the binary convention used in computer science equals how many bytes?

  1. 1048 bytes
  2. 1024 bytes Correct answer.
  3. 1000 bytes
  4. 2048 bytes

Explanation

In binary measurement a kilobyte is 2 raised to the power 10 bytes, which is 1024 bytes. The decimal value 1000 belongs to the SI prefix system, not to the binary convention. Therefore the correct answer is 1024 bytes.

Question 7Computer Fundamentals and Number Systems

Which of the following is an example of system software?

  1. Spreadsheet package
  2. Photo editor
  3. Web browser
  4. Operating system Correct answer.

Explanation

System software manages the hardware and provides a platform on which application programs run; the operating system is the primary example. Spreadsheets, photo editors and web browsers are application software meant for specific user tasks. Hence the operating system alone belongs to the system software category.

Question 8Computer Fundamentals and Number Systems

Which number system uses the digits 0 to 9 together with the letters A to F?

  1. Binary
  2. Decimal
  3. Octal
  4. Hexadecimal Correct answer.

Explanation

The hexadecimal system has base 16, so it needs sixteen symbols: the digits 0 through 9 supply ten and the letters A to F supply the remaining six, standing for values ten to fifteen. Binary uses only 0 and 1, octal uses 0 to 7, and decimal uses 0 to 9. Therefore hexadecimal is the correct system.

Question 9Computer Fundamentals and Number Systems

Convert the decimal number 45 into its binary equivalent.

  1. 101101 Correct answer.
  2. 110101
  3. 111001
  4. 101011

Explanation

Repeated division by two gives remainders 1, 0, 1, 1, 0, 1 read from bottom to top, producing 101101. Checking the place values: 32 + 8 + 4 + 1 = 45. Hence the binary form of forty-five is 101101.

Question 10Computer Fundamentals and Number Systems

What is the hexadecimal equivalent of the binary number 10101111?

  1. A7
  2. 9F
  3. AF Correct answer.
  4. BF

Explanation

Group the bits in fours from the right: 1010 and 1111. The group 1010 equals ten, written A, and 1111 equals fifteen, written F. Joining the two hexadecimal digits gives AF, so AF is the correct conversion.

Question 11Computer Fundamentals and Number Systems

Which logic gate produces a high output only when all of its inputs are high?

  1. AND gate Correct answer.
  2. OR gate
  3. NOR gate
  4. NOT gate

Explanation

The AND gate outputs 1 only when every input is 1; a single low input forces the output low. An OR gate gives 1 when at least one input is high, a NOT gate inverts a single input, and a NOR gate is the inverse of OR. Therefore the AND gate matches the stated condition.

Question 12Computer Fundamentals and Number Systems

Which of the following correctly lists the three basic operations performed by a computer system?

  1. Input, processing and output Correct answer.
  2. Booting, logging in and shutting down
  3. Editing, formatting and printing
  4. Compiling, linking and loading

Explanation

Every computer system fundamentally accepts data, works on it, and presents the result, so input, processing and output form the basic operation cycle. Compilation and linking are programming steps, booting is a startup procedure, and editing or printing are particular application tasks. Only input, processing and output describe the general model.

Question 13Computer Fundamentals and Number Systems

A shopkeeper stores the price of an item as 25 in a computer. In this context, the figure 25 by itself is best described as:

  1. A program
  2. Data Correct answer.
  3. An instruction
  4. Information

Explanation

Data are raw, unprocessed facts and figures that by themselves carry no meaning, and a bare number such as 25 fits this description. Information is the meaningful result obtained after processing, while a program or an instruction is a set of steps for the processor. Hence the figure alone is data.

Question 14Computer Fundamentals and Number Systems

What is the main function of the control unit in a computer's processor?

  1. To hold data being processed temporarily
  2. To coordinate and sequence the operations of the whole system Correct answer.
  3. To convert analogue signals into digital form
  4. To perform arithmetic on numeric operands

Explanation

The control unit fetches instructions, decodes them and generates control signals that direct the other units in the correct order. Arithmetic operations are the job of the arithmetic logic unit, temporary data holding is done by registers, and analogue-to-digital conversion is a function of input hardware. Therefore coordination and sequencing is the control unit's role.

Question 15Computer Fundamentals and Number Systems

Which memory is volatile, meaning its contents are lost when the power supply is switched off?

  1. RAM Correct answer.
  2. Hard disk
  3. ROM
  4. Flash drive

Explanation

RAM is read-write memory that depends on continuous power, so everything stored in it disappears when the machine is switched off. ROM is non-volatile because its contents are fixed during manufacture, and hard disks and flash drives retain data without power. Thus RAM is the volatile memory in the list.

Question 16Computer Fundamentals and Number Systems

The binary number 101.101 has what decimal value?

  1. 5.25
  2. 5.75
  3. 5.625 Correct answer.
  4. 6.125

Explanation

The integer part 101 equals 4 + 0 + 1 = 5. The fractional bits are multiplied by successive negative powers of two: 1×0.5 + 0×0.25 + 1×0.125 = 0.625. Adding the two parts gives 5.625.

Question 17Computer Fundamentals and Number Systems

What is the decimal equivalent of the octal number 157?

  1. 109
  2. 127
  3. 111 Correct answer.
  4. 115

Explanation

Each octal digit is weighted by a power of eight: 1×64 + 5×8 + 7×1. This gives 64 + 40 + 7 = 111. Therefore the octal number 157 equals one hundred eleven in decimal.

Question 18Computer Fundamentals and Number Systems

Which of these correctly represents the decimal number 200 in 8-bit binary form?

  1. 11001000 Correct answer.
  2. 10101000
  3. 11100010
  4. 11010010

Explanation

Subtracting the largest powers of two gives 128 + 64 + 8 = 200, so the bits set are the 128, 64 and 8 positions. Reading from the most significant bit, this yields 11001000. Hence 11001000 is the 8-bit representation of two hundred.

Question 19Computer Fundamentals and Number Systems

Why is hexadecimal notation preferred over binary when programmers inspect memory contents?

  1. Because hexadecimal is the only notation that a processor can execute directly
  2. Because each hexadecimal digit stands for exactly four binary bits, giving a compact form Correct answer.
  3. Because hexadecimal numbers can store negative values while binary cannot
  4. Because hexadecimal arithmetic never produces a carry

Explanation

Four binary bits map to one hexadecimal digit, so a long binary string can be written in a quarter of the length without any loss of information. Binary and hexadecimal both represent the same values and both can be converted to machine code, so the advantage is compactness and readability. Hexadecimal arithmetic follows the same rules as other bases and does produce carries.

Question 20Computer Fundamentals and Number Systems

Which of the following best distinguishes primary memory from secondary memory?

  1. Primary memory is directly accessible by the processor while secondary memory needs input-output channels Correct answer.
  2. Primary memory has a larger capacity than secondary memory
  3. Primary memory stores data permanently while secondary memory is erased at shutdown
  4. Primary memory is cheaper per byte than secondary memory

Explanation

Primary memory such as RAM sits on the processor's direct address path and can be read or written in a few cycles, whereas secondary storage is reached through input-output controllers and is much slower. Secondary memory is cheaper per byte and larger in capacity, and it is the secondary storage that retains data when power is off. Therefore direct accessibility is the distinguishing feature.

Question 21Computer Fundamentals and Number Systems

A byte in memory holds the pattern 11110110. If this pattern is interpreted as a signed integer in 8-bit two's complement form, what decimal value does it represent?

  1. -12
  2. -10 Correct answer.
  3. -9
  4. 246

Explanation

In 8-bit two's complement the leading 1 marks a negative number. Invert all bits to get 00001001 and add one, giving 00001010, which is ten, so the original value is -10. The unsigned reading 246 is not valid once the pattern is treated as signed.

Question 22Computer Fundamentals and Number Systems

A gate has two inputs. Its output is high when the inputs differ and low when they are the same. Which gate is it?

  1. NOR gate
  2. XNOR gate
  3. XOR gate Correct answer.
  4. NAND gate

Explanation

The exclusive-OR gate outputs 1 only when exactly one input is 1, which is precisely the condition that the two inputs differ. XNOR is its complement and outputs 1 when the inputs are equal, while NAND and NOR are negated AND and OR functions. Hence the described behaviour belongs to the XOR gate.

Question 23Computer Fundamentals and Number Systems

What is the result of adding the binary numbers 1011 and 1101, expressed in binary?

  1. 10110
  2. 11000 Correct answer.
  3. 11010
  4. 10010

Explanation

In decimal the operands are 11 and 13, whose sum is 24. Converting 24 to binary gives 16 + 8 = 11000. Column-wise addition with carries confirms this: the four-bit sum overflows into a fifth bit, producing 11000.

Question 24Computer Fundamentals and Number Systems

A computer's memory is byte-addressable and a program needs to store a 32-bit integer starting at address 2000. Assuming the integer occupies consecutive bytes, what is the address of its last byte?

  1. 2004
  2. 2032
  3. 2002
  4. 2003 Correct answer.

Explanation

A 32-bit integer occupies 32 divided by 8, that is four bytes. The bytes therefore sit at addresses 2000, 2001, 2002 and 2003, so the last byte is at 2003. Adding four to the start address gives the address just past the value, not the last byte itself.

Question 25Hardware, Software and Operating System Basics

Which component of a computer system is described as the main circuit board that connects the CPU, RAM and other devices?

  1. Motherboard Correct answer.
  2. Power supply unit
  3. Optical drive
  4. Hard disk drive

Explanation

The motherboard is the primary printed circuit board inside a computer. It provides the sockets, slots and buses through which the CPU, RAM, expansion cards and storage interfaces communicate with one another.

Question 26Hardware, Software and Operating System Basics

Which type of software is an operating system such as Windows or Linux classified as?

  1. System software Correct answer.
  2. Application software
  3. Firmware stored in ROM
  4. Utility driver

Explanation

An operating system is system software because it manages hardware resources and provides services for application programs. Application software, by contrast, is written to perform user-oriented tasks.

Question 27Hardware, Software and Operating System Basics

In a computer, which unit performs arithmetic calculations and logical comparisons?

  1. Input unit
  2. Main memory
  3. Arithmetic Logic Unit Correct answer.
  4. Control unit

Explanation

The Arithmetic Logic Unit, or ALU, is the part of the CPU that carries out arithmetic operations such as addition and logical operations such as comparisons. The control unit directs operations rather than performing them.

Question 28Hardware, Software and Operating System Basics

Which of the following is an example of secondary storage?

  1. Register
  2. Random access memory
  3. Solid-state drive Correct answer.
  4. Cache memory

Explanation

Secondary storage holds data permanently or semi-permanently and is non-volatile, and a solid-state drive is a typical example. Registers, cache and RAM are all primary memory that loses its contents when power is removed.

Question 29Hardware, Software and Operating System Basics

Which of these is a function commonly performed by an operating system?

  1. Editing a photograph
  2. Compiling source code into machine code
  3. Designing graphics for a web page
  4. Managing files and directories on storage Correct answer.

Explanation

File management is a core operating-system service: the OS organises, stores and retrieves files on storage devices. Compilation, graphics design and photo editing are tasks done by application programs.

Question 30Hardware, Software and Operating System Basics

Which memory is volatile, meaning its contents are lost when the computer is switched off?

  1. Hard disk
  2. RAM Correct answer.
  3. ROM
  4. Flash drive

Explanation

RAM is volatile memory: it holds programs and data only while power is supplied. ROM, hard disks and flash drives retain their contents without power.

Question 31Hardware, Software and Operating System Basics

A student wants to run two operating systems on one computer and choose between them at startup. Which software makes this selection possible?

  1. Bootloader Correct answer.
  2. Compiler
  3. Antivirus utility
  4. Device driver

Explanation

A bootloader runs when the machine powers on and loads the chosen operating system, so a multi-boot bootloader lets the user pick between installed systems. Device drivers and utilities run after an OS has started.

Question 32Hardware, Software and Operating System Basics

Which scheduling or system concept allows several programs to appear to run at the same time on a single CPU by rapidly switching between them?

  1. Spooling
  2. Paging
  3. Multitasking Correct answer.
  4. Buffering

Explanation

Multitasking gives each process a short slice of CPU time and switches rapidly among them, creating the impression of simultaneous execution. Spooling, paging and buffering address I/O and memory management rather than CPU sharing among programs.

Question 33Hardware, Software and Operating System Basics

A user installs a new printer but it does not work until a small program supplied by the manufacturer is installed. What is this program called?

  1. Utility suite
  2. Operating system kernel
  3. Device driver Correct answer.
  4. Shell

Explanation

A device driver is the software that translates operating-system commands into instructions the specific hardware understands. Without the correct driver, the OS cannot properly control the printer.

Question 34Hardware, Software and Operating System Basics

Which of the following best describes the role of the kernel in an operating system?

  1. It provides the graphical desktop and icons.
  2. It stores user documents permanently.
  3. It translates high-level languages into machine code.
  4. It manages memory, processes and hardware access at the core level. Correct answer.

Explanation

The kernel is the central part of the operating system that controls memory allocation, process scheduling and access to hardware. User interfaces and applications sit above it and request services from it.

Question 35Hardware, Software and Operating System Basics

Which unit of storage is equal to 1024 megabytes?

  1. 1 kilobyte
  2. 1 byte
  3. 1 terabyte
  4. 1 gigabyte Correct answer.

Explanation

In binary storage measurement, 1024 megabytes make one gigabyte. Each step upward multiplies by 1024: kilobytes to megabytes, megabytes to gigabytes, and gigabytes to terabytes.

Question 36Hardware, Software and Operating System Basics

What is the main advantage of a GUI over a command-line interface for a beginner?

  1. It can only be used by system administrators.
  2. It uses fewer system resources than any other interface.
  3. It allows tasks to be performed using icons and menus instead of memorised commands. Correct answer.
  4. It removes the need for an operating system.

Explanation

A graphical user interface presents windows, icons and menus that the user can click, so commands need not be memorised. This makes it easier for beginners, though it generally uses more resources than a text interface.

Question 37Hardware, Software and Operating System Basics

Which statement correctly distinguishes system software from application software?

  1. Application software runs without an operating system, while system software needs one.
  2. System software helps run the computer itself, while application software helps the user perform specific tasks. Correct answer.
  3. System software is always free, while application software is always paid.
  4. Application software is stored in ROM, while system software is stored on disk.

Explanation

System software, such as the operating system and utilities, manages and controls the computer's hardware and provides a platform. Application software uses that platform to carry out user tasks such as writing or browsing.

Question 38Hardware, Software and Operating System Basics

Which of these is a valid example of an open-source operating system?

  1. Linux Correct answer.
  2. macOS
  3. MS-DOS
  4. Microsoft Windows 11

Explanation

Linux is distributed with source code that anyone may inspect, modify and redistribute under licences such as the GPL, so it is open source. Windows, macOS and MS-DOS are proprietary systems.

Question 39Hardware, Software and Operating System Basics

A file of 5 MB is copied to a drive that has only 3 MB of free space. What will most likely happen?

  1. The file will be automatically split across drives.
  2. The copy will complete because compression is automatic.
  3. The copy will fail or report insufficient space. Correct answer.
  4. The file will be converted to a smaller format.

Explanation

An operating system checks free space before writing a file; if the destination lacks enough room, the copy operation fails and an error such as 'insufficient disk space' is shown. Automatic compression or splitting is not a default behaviour.

Question 40Hardware, Software and Operating System Basics

Why does adding more RAM generally improve the performance of a computer running many programs?

  1. It increases the capacity of the hard disk.
  2. It reduces the need to swap data to slower secondary storage. Correct answer.
  3. It replaces the need for a device driver.
  4. It increases the clock speed of the processor.

Explanation

With more RAM, more programs and data can stay in fast main memory, so the operating system swaps less to slower disk storage. This reduces delays caused by virtual-memory paging.

Question 41Hardware, Software and Operating System Basics

A programmer writes a program in a high-level language. Which software converts the entire source file into machine code before it is run?

  1. Interpreter
  2. Compiler Correct answer.
  3. Assembler
  4. Linker

Explanation

A compiler translates the whole source program into object or machine code in one pass before execution. An interpreter, by contrast, translates and executes statement by statement.

Question 42Hardware, Software and Operating System Basics

Which statement about the relationship between hardware and software in a computer system is most accurate?

  1. Software instructs the hardware, and hardware executes those instructions. Correct answer.
  2. Hardware can execute instructions without any software.
  3. Software physically stores data in RAM without hardware assistance.
  4. Hardware and software are independent and never interact.

Explanation

Software is a set of instructions, and hardware is the physical circuitry that carries them out. Neither can perform useful computation alone: the software directs operations and the hardware executes them.

Question 43Hardware, Software and Operating System Basics

In a system using virtual memory, what is the purpose of a page fault?

  1. It permanently damages the RAM module.
  2. It indicates that the CPU clock is too fast.
  3. It signals that a requested page is not currently in RAM and must be loaded. Correct answer.
  4. It deletes the file that caused the error.

Explanation

A page fault occurs when a program references a page that is not presently in physical memory. The operating system then loads the needed page from secondary storage into RAM and resumes execution.

Question 44Hardware, Software and Operating System Basics

Which combination correctly pairs a volatile memory with a non-volatile storage medium?

  1. Cache with registers
  2. ROM with a flash drive
  3. RAM with a hard disk Correct answer.
  4. RAM with ROM

Explanation

RAM is volatile memory that loses its contents on power-off, while a hard disk is non-volatile secondary storage that keeps data. The other pairs do not combine one volatile and one non-volatile item correctly.

Question 45Windows and GUI Operations

In the Windows GUI, which part of a standard window contains the Minimize, Maximize and Close buttons?

  1. The status bar
  2. The title bar Correct answer.
  3. The menu bar
  4. The scroll bar

Explanation

The title bar runs across the top of a window and displays the window title together with the control buttons for minimizing, maximizing and closing. The status bar sits at the bottom, the scroll bar at the side, and the menu bar holds command menus rather than window controls.

Question 46Windows and GUI Operations

A file named report.txt is currently open in Notepad. Which action renames the file without changing its contents?

  1. Double-click the file icon in File Explorer
  2. Open the file and use File > Save As with the same name
  3. Drag the file icon onto the Recycle Bin
  4. Right-click the file in File Explorer and choose Rename, then type a new name Correct answer.

Explanation

Renaming through the context menu changes only the file name in the file system; the stored data is untouched. Save As with the same name would rewrite the file, and the other actions either delete or open it.

Question 47Windows and GUI Operations

What is the main purpose of the Recycle Bin in Windows?

  1. To compress large files to save disk space
  2. To hold deleted files temporarily so they can be restored Correct answer.
  3. To store the operating system's backup copies
  4. To permanently erase files as soon as they are deleted

Explanation

Deleted files from local drives are moved to the Recycle Bin rather than destroyed, allowing the user to restore them. They remain there until the bin is emptied or the file is removed from it.

Question 48Windows and GUI Operations

Which keyboard shortcut switches between open application windows in Windows?

  1. Shift + Delete
  2. Ctrl + C
  3. Alt + Tab Correct answer.
  4. Ctrl + P

Explanation

Alt + Tab displays the open windows and lets the user cycle to another one. Ctrl + C copies, Ctrl + P prints, and Shift + Delete bypasses the Recycle Bin.

Question 49Windows and GUI Operations

On a Windows desktop, what happens when you double-click a folder icon?

  1. The folder is copied to the clipboard
  2. The folder is renamed to New Folder
  3. A window opens showing the folder's contents Correct answer.
  4. The folder is deleted from the desktop

Explanation

A folder is a container, so double-clicking it opens an Explorer window that lists the files and subfolders inside. Double-clicking does not delete, rename, or copy the folder.

Question 50Windows and GUI Operations

A student wants to select several non-adjacent files in a folder using the mouse and keyboard. Which method works?

  1. Hold Ctrl and click each required file one by one Correct answer.
  2. Drag a rectangle around all files in the folder
  3. Press Ctrl + A once
  4. Click the first file, then hold Shift and click the last file

Explanation

Holding Ctrl while clicking adds or removes individual files from the selection, which is how non-adjacent items are chosen. Shift-clicking and rectangle dragging select ranges or blocks of adjacent items, and Ctrl + A selects everything.