Basic computer operations (hardware and software)

The scroll wheel is the mouse component used to move through a page vertically. Rotating it forward or backward sends a scrolling command, causing the displayed content to move up or down. The left button normally selects or opens items, the right button usually displays a context menu, and the cable only connects the mouse. Therefore, the scroll wheel is the correct answer.

The Copy command places a duplicate of selected text, an image, or another item on the clipboard while leaving the original unchanged in its current location. The duplicate is normally inserted elsewhere with Paste. Cut is different because it removes the selected content from its original position for moving; Delete removes it, and Close exits a window or document rather than duplicating content.

Redo reapplies an action that was previously reversed with Undo. For instance, after undoing a typed sentence or formatting change, Redo can restore that action if the user decides it was needed. Cut removes selected content, Find searches for text or items, and Close exits a window or document. Thus Redo, not those commands, performs the required operation; many programs provide Ctrl+Y or another Redo shortcut.

Ctrl+A is the common keyboard shortcut for selecting all available content in the active document, text box, or supported window. After selecting everything, the user can copy, format, delete, or move the selection as needed. Ctrl+S saves, Ctrl+P usually opens printing, and Ctrl+Z undoes the previous action. The letter A can be remembered as the first letter of “All.”

Ctrl+S commonly activates the Save command in computer applications, so option A is correct. Ctrl+X cuts selected content, Ctrl+V pastes it, and Ctrl+A selects all content.

Ctrl+C copies selected content to the clipboard without removing it from its original location, so option B is correct. Ctrl+V pastes, Ctrl+X cuts, and Ctrl+P commonly opens the print command.

Ctrl+V performs the Paste command, placing clipboard content at the active location, so option C is correct. Ctrl+Z commonly undoes an action, Ctrl+C copies, and Ctrl+S saves.

Ctrl+X cuts selected content by removing it from its current location and placing it on the clipboard, so option D is correct. Ctrl+C copies without removing, Ctrl+A selects all, and Ctrl+S saves.

Antivirus software can detect known or suspected malicious software and may warn about, quarantine, or remove detected threats. It helps protect a computer, though it cannot guarantee that every threat will be stopped. A calculator, Paint, and a word processor have different main purposes.

An application from an unknown source may contain malware or request unsafe permissions. Check whether the source and publisher are trustworthy, and pay attention to security warnings before installing it. Therefore, option B is correct.

Installing an application copies or configures the program and its required components on the computer so the operating system can run it. Therefore, the process is called installation.

Uninstallation removes an installed application, usually through the operating system or the program’s removal tool. Deleting a desktop shortcut alone may not remove the application, so the correct answer is uninstallation.

Updating means applying a newer version or changes to existing software. An update may fix errors, improve security, or add features, so option A is correct.

Close any open files and use the operating system’s Safely Remove or Eject command before disconnecting the device. This lets pending activity finish and reduces the risk of file or data corruption, so option B is correct.

The governing concept is the graphical user interface, in which visual symbols represent digital objects or commands. A small picture used to represent a file, folder, application, or action is called an icon, so option A is correct. A folder stores files, a cursor shows the pointer or insertion position, and a menu presents a list of commands; none of these specifically means the small identifying symbol.

The desktop is the main working area that normally appears after the operating system starts and the user signs in. It may contain icons, a background, and the taskbar, so option B is correct. The taskbar provides shortcuts and running-application controls, the title bar identifies a window, and the scroll bar moves content within a window; none is the complete main screen.

The governing concept is the distinction between hardware and software. Software consists of programs and instructions that tell the computer how to perform tasks, so option B is correct. Hardware means the physical parts that can be touched, while a monitor displays output and a keyboard supplies input. These devices work with software but are not instruction sets themselves.

The governing concept is safe computer operation. The Shut down command closes active system processes in an orderly way and then powers off the computer. Therefore, option A is correct. Save As stores a file under a chosen name, Copy duplicates selected content, and Print produces a paper or digital printout; none of these turns the computer off safely.

The governing concept is clipboard-based editing. Copy places a duplicate of the selected text, image, or file on the clipboard while leaving the original unchanged in its current location. Hence, option B is correct. Cut removes the selection for relocation, Delete removes it, and Rename changes only its identifying name rather than duplicating its content.

The governing concept is moving content through the clipboard. Cut removes the selected text, image, or file from its current location and places it on the clipboard; Paste can then insert it at another location. Therefore, option C is correct. Copy leaves the original in place, Save stores changes, and Open loads a file.

The governing concept is using the clipboard to insert content. Paste takes data previously placed on the clipboard by Copy or Cut and inserts it at the selected cursor position or destination. Thus, option D is correct. Rename changes a name, Delete removes an item, and Print produces an output; none places clipboard content in a new location.

The governing concept is keyboard input. In a text editor, pressing Enter moves the insertion point to a new line; in many interfaces it can also confirm a selected command. Spacebar inserts a blank space, Backspace removes text to the left, and Tab moves to the next field or adds indentation. Therefore A is correct.

The governing concept is text entry with a keyboard. Pressing the Spacebar inserts a blank space at the cursor position, which separates adjacent words. Shift is used for capital letters or upper symbols, Escape usually cancels or exits an action, and Control works with shortcut combinations. Thus option B is the correct choice.

The governing concept is positional text editing. Backspace removes the character immediately to the left of the cursor, so it is useful for correcting text already typed. Delete generally removes the character to the right of the cursor or a selected item, Enter creates a line, and Tab moves focus or adds indentation. Therefore option C is correct.

The governing concept is keyboard case control. When Caps Lock is switched on, alphabetic keys normally produce uppercase letters continuously until Caps Lock is pressed again. Enter starts a line, Spacebar inserts a gap, and Tab moves focus or creates indentation. Shift can produce one capital letter when held, but option D is designed for continuous capitals.