Basic components of a computer system

Correct answer: A. A report is displayed on the screen and a paper copy is printed

Explanation: The governing concept is the distinction between input and output devices. A monitor sends processed information to the user as visual output, while a printer sends it as a physical paper copy. In option A, the same report is therefore presented through both output forms. A keyboard, microphone, and camera primarily send data into the computer, so options B, C, and D do not show both devices acting as outputs.

Correct answer: C. Keyboard

Explanation: An input device sends data or commands from the user to the computer. A keyboard accepts letters, numbers, and control commands, so option C is correct. A monitor displays visual output, a printer produces a paper output, and speakers produce audio output. Therefore, the keyboard is the only option that primarily supplies user input in this list.

Correct answer: D. Monitor

Explanation: The governing input-output concept is that an output device presents processed information to the user. A monitor displays text, pictures, graphics, and video on the screen, so option D is correct. A mouse and keyboard send commands or data into the computer, while a scanner converts paper images or documents into digital input. Thus only the monitor displays the computer’s visual results.

Correct answer: B. Printer

Explanation: The governing concept is output hardware. A printer receives digital text or images from the computer and produces a physical paper copy, commonly called a hard copy, so option B is correct. A scanner performs the reverse type of task by capturing paper content as digital input; a monitor shows a soft copy on screen, and a microphone records sound as input.

Correct answer: D. Speaker

Explanation: The governing concept is audio output. A speaker converts the computer’s electrical or digital audio signal into sound that a person can hear, so option D is correct. A keyboard and mouse are input devices used to enter commands, while a webcam captures images or video as input. Therefore, the speaker is the only listed device whose primary purpose is delivering audible computer output.

Correct answer: A. Microphone

Explanation: The governing concept is audio input: an input device sends information into the computer for recording or processing. A microphone changes spoken sound into an electrical or digital signal that the computer can store, so option A is correct. A monitor, printer, and projector are output devices that present information visually or on paper; they do not primarily capture a user’s voice.

Correct answer: B. Capturing images and video

Explanation: The governing concept is visual input. A webcam is a camera-based input device that captures still images and moving video and sends that visual information to the computer, so option B is correct. Printing documents is the work of a printer, calculations are handled by processing hardware and software, and deleting files is an operating-system command rather than the webcam’s function.

Correct answer: C. Central Processing Unit

Explanation: The governing concept is computer processing. The Central Processing Unit, or CPU, interprets and executes instructions and coordinates many operations, so option C is correct. A monitor produces visual output, a mouse sends user input, and a speaker produces audio output. Although modern computers contain several specialized processors, the CPU remains the standard school-level name for the main processing unit.

Correct answer: B. Desktop

Explanation: The governing concept is the graphical user interface of an operating system. After startup and sign-in, the desktop is the main workspace where icons, the taskbar, and windows can be accessed. Thus, option B is correct. A folder stores files, while a printer and scanner are hardware devices, so they are not the main screen.

Correct answer: D. Monitor

Explanation: The governing concept is the distinction between input and output devices. An output device presents information processed by the computer to the user. A monitor displays text, pictures, video, and other results, so option D is correct. A mouse, keyboard, and scanner send user actions or captured information into the computer, making them input devices rather than output devices. The device’s function, not its physical size, determines the category.

Correct answer: A. Central Processing Unit

Explanation: The governing concept is the function of the Central Processing Unit, or CPU. It fetches, interprets, and executes instructions and performs calculations and control operations, so it is commonly called the brain of the computer. Option A is correct. A mouse sends input, a monitor displays output, and a printer produces a printed output; none of these centrally processes the computer’s instructions like the CPU does.

Correct answer: C. Monitor

Explanation: The governing concept is identifying computer components by their function. The screen is called a monitor, and it displays processed text, images, video, and other visual results; therefore option C is correct. A keyboard enters typed data, a scanner captures printed or visual information, and a microphone captures sound. These are input devices, whereas the monitor presents output to the user.

Correct answer: B. To remove content from one place and move it to another

Explanation: The governing concept is moving content through the Cut-and-Paste operation. Cut removes the selected content from its current place and stores it temporarily on the clipboard; Paste can then insert it at another location. Thus option B is correct. Copy also uses the clipboard, but it leaves the original in place. Printing, opening a file, and shutting down the computer are unrelated commands.

Correct answer: B. To save a file with a new name or location

Explanation: The governing concept is creating a separately named or located version of a file. Save As opens choices for a new file name, format, or destination, so the original file can remain unchanged while another version is stored. Therefore option B is correct. Ordinary Save updates the current file, whereas starting the computer, deleting a file, and moving a mouse are unrelated actions and do not describe Save As.

Correct answer: C. A context menu of options

Explanation: A right-click usually opens a context menu containing commands related to the selected item or location. Depending on where the pointer is placed, the menu may offer actions such as Open, Copy, Rename, Properties, or Paste. Therefore, option C is correct. It does not automatically print, shut down the computer, or remove the screen. The available commands can vary with the selected object.

Correct answer: B. To reduce the risk of data corruption

Explanation: The governing concept is safe removal of external storage. The operating system may still be reading from or writing to a pen drive, even when no obvious activity is visible. Using Safely Remove allows pending operations and file-system updates to finish before the device is disconnected. Option B is correct because it reduces corruption and data-loss risk; the other options are unrelated to storage safety.

Correct answer: A. Motherboard

Explanation: The governing concept is the role of internal computer hardware. The motherboard is the main printed circuit board that provides connections and communication pathways for components such as the processor, memory, storage interfaces, and expansion devices. Therefore, option A is correct. A mouse pad supports a mouse, a monitor displays output, and a speaker produces sound; none connects the internal components as the main board.

Correct answer: C. Arithmetic Logic Unit

Explanation: The governing concept is the division of functions within the central processing unit. The arithmetic logic unit, or ALU, performs arithmetic operations such as addition and subtraction and logical comparisons such as greater than or equal to. Therefore option C is correct. The control unit directs operations, the hard disk stores data, and the power supply provides electrical power rather than calculating results.

Correct answer: D. Coordinate computer operations

Explanation: The governing concept is the control unit's role inside the CPU. It fetches and interprets instructions, then sends control signals so that the processor, memory, and input-output devices perform their tasks in the correct order. Thus option D is correct. Displaying images and recording sound are device functions, while permanent file storage belongs to storage hardware, not the control unit.

Correct answer: A. Ports

Explanation: The governing concept is computer hardware connectivity. A port is a physical connection point through which a computer communicates with an external device, such as a keyboard, printer, monitor, or USB drive. Therefore, option A is correct. Folders organize files, windows display software or documents, and icons represent items on the screen; none of these is a physical device connection point.

Correct answer: B. Connect devices and transfer data

Explanation: The governing concept is the function of a USB interface. A USB port can connect peripherals such as keyboards, mice, printers, and flash drives, and it can carry digital data between the computer and a connected device. Hence option B is correct. Sound may sometimes pass through a USB device, but hearing sound alone is not its defining use; screen brightness and cooling are unrelated functions.

Correct answer: C. Connect major computer components

Explanation: The governing concept is the architecture of a computer system. The motherboard is the main circuit board that provides pathways and connections among the processor, memory, storage interfaces, expansion cards, and other components. Thus option C is correct. Printing is performed through a printer, internet access requires network hardware and software, and sound production is handled by audio hardware rather than being the motherboard’s sole function.

Correct answer: D. Supply required power to components

Explanation: The governing concept is electrical power management in computer hardware. A power supply unit receives electricity from an external source, converts it into suitable forms and voltages, and distributes it to internal components such as the motherboard, drives, and fans. Therefore option D is correct. Scanning, renaming files, and drawing images are performed by peripherals or application software, not by the power supply unit.

Correct answer: A. Cooling Fan

Explanation: The governing concept is thermal management. A cooling fan moves air through or across the computer case and helps carry heat away from components such as the processor and power supply. Consequently, option A is correct. A webcam captures video, a microphone captures sound, and a scanner converts physical images or text into digital form; none of these devices is designed to remove heat. Clean vents also support effective cooling.

Correct answer: B. Uninterruptible Power Supply

Explanation: The governing concept is backup power protection. An uninterruptible power supply, or UPS, contains a battery and supplies electricity for a limited period when the main power fails. This short interval allows a user to save work and shut down the computer safely. Therefore option B is correct. A modem and router handle network communication, while a projector displays images; neither normally provides the computer’s backup electricity.