The Melissa virus, which emerged in 1999, was a fast-spreading macro virus primarily disseminated through email attachments, making it an E-mail virus.

John Vincent Atanasoff, along with Clifford Berry, is credited with inventing the Atanasoff–Berry Computer, an early electronic digital computer.

ISP (Internet Service Provider) is a company or organization that provides individuals, businesses, and institutions with access to the Internet. An ISP offers services such as broadband, fiber-optic, DSL, cable, wireless, and mobile Internet connections. In addition to Internet access, many ISPs also provide email accounts, web hosting, domain registration, cloud storage, and cybersecurity services. Users subscribe to an ISP and connect to the Internet through devices such as modems, routers, or fiber-optic terminals. Examples of ISPs include PTCL, Nayatel, StormFiber, Optix, and various mobile network operators that offer 4G and 5G Internet services.

An ISP acts as the gateway between a user's device and the global Internet by routing data packets across networks. The quality of an ISP is often measured by its download and upload speeds, reliability, coverage, customer support, and pricing. Modern ISPs use advanced networking technologies to ensure secure and high-speed connectivity for activities such as web browsing, online learning, video streaming, cloud computing, online gaming, and video conferencing. Choosing a reliable ISP is essential for maintaining a stable and efficient Internet connection.

Why the other options are incorrect:

• Internal Server Provider is not the official expansion of the acronym ISP and is not a recognized networking term.
• Internet Server Provider is an incorrect variation because ISPs provide Internet access rather than functioning solely as server providers.
• Insta Service Provider is not a valid or recognized expansion of ISP in computer networking.

The keyboard shortcut Ctrl+Shift+N is universally used on Windows operating systems to quickly create a new folder in the current directory.

The CPU, or Central Processing Unit, is the fundamental hardware component responsible for executing instructions and performing all data processing operations within a computer system.

CSS stands for Cascading Style Sheets. It is a stylesheet language used to control the appearance and layout of web pages created with HTML. CSS allows web developers to define colors, fonts, spacing, borders, backgrounds, animations, and the positioning of elements, making websites visually attractive and responsive across different devices.

The term \"Cascading\" refers to the way CSS applies styles according to a hierarchy or priority. When multiple style rules exist for the same element, the browser determines which rule takes precedence based on specificity, importance, and source order. This feature makes CSS flexible and efficient for managing the design of large websites.

CSS works alongside HTML but serves a different purpose. While HTML provides the structure and content of a webpage, CSS controls its presentation and design. Modern websites rely heavily on CSS frameworks such as Bootstrap and Tailwind CSS to create responsive layouts quickly. Therefore, the correct expansion of CSS is Cascading Style Sheets, making Option B the correct answer.

Full-duplex mode enables simultaneous two-way communication, allowing data to be sent and received over a channel at the exact same time.

Microprocessors are versatile integrated circuits that serve as the central processing unit in computers, digital devices, and calculators, enabling their operations.

Among the given options, the correct answer is "None of the above" because the smallest commonly used unit of digital storage is not listed. In computer systems, data is measured using units such as bit, byte, kilobyte (KB), megabyte (MB), gigabyte (GB), and terabyte (TB). A bit is the smallest unit of data, while a byte consists of 8 bits. Since all the listed options begin with a megabyte or larger, none represents the smallest storage unit. Therefore, "None of the above" is the correct choice.

Storage units increase in size in the following order: Bit → Byte → Kilobyte (KB) → Megabyte (MB) → Gigabyte (GB) → Terabyte (TB) → Petabyte (PB). Approximately 1,024 KB = 1 MB, 1,024 MB = 1 GB, and 1,024 GB = 1 TB (binary measurement commonly used in computing). Understanding these storage units is essential for computer literacy and is a frequently tested topic in competitive examinations related to information technology and general computer knowledge.

Why the other options are incorrect:

• Megabyte (MB) is larger than a kilobyte and a byte, so it is not the smallest storage unit.
• Gigabyte (GB) is much larger than a megabyte and is commonly used to measure the storage capacity of hard drives, SSDs, and memory cards.
• Terabyte (TB) is larger than both gigabytes and megabytes and is used to measure the capacity of modern storage devices.

Right-clicking an object typically opens a context menu, providing quick access to its properties and relevant actions.

Computer forensics is the specialized field focused on recovering and investigating data from digital devices for legal purposes.

COBOL stands for Common Business-Oriented Language, a high-level programming language primarily used for business applications.

Random access allows a device to directly locate and retrieve specific data without needing to read through preceding data sequentially.

An operating system performs various crucial functions including allocating resources, monitoring activities, and managing disks and files.

Dennis Ritchie is widely credited as the creator of the C programming language, developing it at Bell Labs in the early 1970s.

DOS stands for Disk Operating System, a family of operating systems that were widely used from the early 1980s to the mid-1990s.

Modern computers are highly reliable, but they are not infallible, meaning they can still experience errors, bugs, or hardware malfunctions.

First-generation computers, utilizing vacuum tubes, were characterized by their extremely large physical size, often occupying entire rooms due to their components.