Computer MCQs for Competitive Exams

JPEG stands for Joint Photographic Experts Group, the international committee that developed one of the most widely used standards for digital image compression. The JPEG format was created to reduce the file size of digital photographs while maintaining acceptable image quality, making it ideal for storing and sharing images over the internet.

JPEG uses a lossy compression technique, which means some image data is permanently removed to achieve smaller file sizes. Users can choose different compression levels depending on the balance they want between image quality and storage space. Because of its efficient compression, JPEG is commonly used for photographs, web images, digital cameras, and social media platforms.

Although JPEG is excellent for photographs and colorful images, it is not the best choice for graphics containing sharp lines, text, or logos because repeated editing and saving can reduce image quality. Since the abbreviation is officially derived from the committee that developed the standard, Joint Photographic Experts Group is the correct expansion, making Option C the correct answer.

BASIC (Beginner's All-purpose Symbolic Instruction Code) is a high-level programming language developed in 1964 by John G. Kemeny and Thomas E. Kurtz at Dartmouth College. It was designed to make programming simple and accessible for beginners, students, and non-technical users. At a time when programming languages were complex and mainly used by scientists and engineers, BASIC introduced an easy-to-understand syntax that allowed users to write programs with minimal training. It became one of the most popular programming languages for personal computers during the 1970s and 1980s.

BASIC supports fundamental programming concepts such as variables, arithmetic operations, conditional statements, loops, functions, and input/output operations. Many early home computers, including systems from Apple, Commodore, and IBM, included a BASIC interpreter built into their operating systems, making it one of the first programming languages learned by millions of users. Modern versions, such as Visual Basic and Visual Basic .NET (VB.NET), have expanded the language with graphical user interface (GUI) development, object-oriented programming, and integration with the Microsoft .NET framework.

Why the other options are incorrect:

• Basic All-purpose Standard Instruction Code is not the official expansion of BASIC.
• Beginner's All-purpose System Instruction Code is an incorrect variation and has never been the accepted full form.
• Basic All-purpose Symbolic Input Code is not a recognized expansion of the acronym BASIC.

The correct answer is Ctrl+Shift+6 because this built-in shortcut combination instantly applies the Scientific (exponential) number format to the active cells.

• Ctrl+Shift+6: This is the correct choice. On a standard keyboard layout, the number 6 key houses the caret symbol (^), meaning this command is also represented as Ctrl + Shift + ^. Executing it converts long digits into scientific notation displaying a decimal value followed by an 'E' exponent parameter (e.g., 120,000 becomes 1.20E+05) to easily manage large numerical figures.
• Incorrect Options:
  • Ctrl+Shift+3: This is incorrect. This combination applies the Date format (day, month, and year) to selected cell values.
  • Ctrl+Shift+4: This is incorrect. This shortcut applies the Currency format (using the dollar/local currency symbol with two trailing decimal places).
  • Ctrl+Shift+5: This is incorrect. This command applies the Percentage format with no trailing decimal representation.

PNG (Portable Network Graphics) is a widely used raster image file format developed as an improved, patent-free alternative to the GIF format. Introduced in 1996, PNG supports lossless compression, meaning image quality is preserved even after repeated saving and editing. It is commonly used for logos, icons, screenshots, illustrations, and web graphics because it provides sharp image quality and supports transparent backgrounds through alpha channels. PNG files are compatible with virtually all modern web browsers, image editing software, and operating systems, making them one of the most popular image formats on the Internet.

Unlike JPEG, which uses lossy compression and may reduce image quality, PNG retains every detail of the original image, making it ideal for graphics containing text, diagrams, and line art. However, because PNG files preserve all image data, they are generally larger than JPEG files and are therefore less suitable for storing high-resolution photographs. The format is maintained by the PNG Development Group and has become a standard choice for web designers, developers, and digital artists who require high-quality images with transparency support.

Why the other options are incorrect:

• Portable Network Group is not the correct expansion of the acronym PNG and is not a recognized image format.
• Project Network Graphics is an incorrect variation and has never been the official full form of PNG.
• Plain Network Graphics is not a valid computer graphics term or the accepted expansion of PNG.

Data manipulation by computers is fundamentally known as processing, transforming raw input into meaningful output.

A hacker is an individual who uses their technical skills to illegally access computer systems, often for malicious purposes or unauthorized information retrieval.

RAM (Random Access Memory) is volatile memory, meaning it only stores data temporarily while the computer is powered on, unlike permanent storage devices.

Malware is a broad term encompassing any software specifically designed to disrupt, damage, or gain unauthorized access to a computer system.

A firewall is a security system, either hardware or software, that monitors and controls network traffic to prevent unauthorized access to a computer.

Mainframe computers are powerful, large-scale machines primarily used by large organizations for critical applications and bulk data processing.

NOS stands for Network Operating System, which is specialized software designed to manage network resources and facilitate communication between connected devices.

A hyperlink is a clickable element on a webpage that directs the user to another document, section, or resource when activated.

A programming language is a formal set of instructions and rules used to tell a computer what operations to perform, enabling software development.

The memory unit is an essential component of the Central Processing Unit (CPU), responsible for storing data and instructions for quick access.

Serial access memories are most useful in applications where data is inherently processed or stored sequentially, flowing in and out serially.

Debugging is the essential process of identifying, analyzing, and fixing or bypassing errors within computer program code to ensure proper operation.

BIOS is an acronym for Basic Input Output System, which is firmware used to perform hardware initialization during the booting process.

Sorting is the process of arranging data elements into a specific order or sequence, such as alphabetical or numerical, for better organization.

RAM functions as a "waiting room" for the computer's processor, temporarily holding data and instructions ready for immediate access and processing.

Thomas J. Watson Sr. is recognized as the founder of IBM, having built the company into a global technology and consulting corporation.

A keyboard or mouse is an input device, which allows users to feed data and commands into a computer system for processing.

In Microsoft Word, a document can be saved using "Save," "Save As," or through the quick access toolbar, providing three distinct methods.

The correct answer is submenu because a submenu acts as a secondary, branching level within a hierarchical user interface menu system to display specialized options related to a primary selection.

• submenu: This is the correct choice. Your original default answer key listed 'dialog box', which is a factual error. In classic graphical user interfaces, when a user expands a primary option from the main menu bar (such as 'File' or 'Edit'), a drop-down list appears. Choosing an entry marked with a secondary arrow opens a 'submenu', presenting an additional, clustered set of related parameters or commands.
• Incorrect Options:
  • dialog box: This is incorrect. A dialog box is an independent, standalone pop-up window that prompts users to input parameter values, choose specific settings, or view system confirmation notifications before a program can proceed. It is not an integrated extension of the main menu list itself.
  • menu selection: This is incorrect. This is a general descriptive term for the act of clicking an option rather than a distinct interface element or structural command group.

MS-Access is a relational database management system (RDBMS) designed for creating, managing, and manipulating databases, making it a database program.

In MS Excel, the "Data" tab contains the "Remove Duplicates" feature, which is specifically used to delete duplicate values from a selected range.