Computer Awareness & Fundamentals — Set 05
Standard: OSSSC, OSSC, Odisha Police, Banking, SSC CGL/CHSL, Railways & Teaching Exams | 50 Fresh Basic-Level MCQs.
1. Who among the following conceived and designed the 'Stored-Program Concept' architecture (EDVAC) followed by modern computers?
- A) Alan Turing
- B) John von Neumann
- C) Blaise Pascal
- D) Herman Hollerith
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Correct Answer: B) John von Neumann
Explanation: In 1945, mathematician John von Neumann introduced the stored-program concept, proposing that program instructions and data share the same read-write primary memory space.
2. Herman Hollerith developed punched card tabulating machinery in the late 19th century that eventually evolved into which technology corporation?
- A) Apple
- B) Microsoft
- C) IBM (International Business Machines)
- D) Hewlett-Packard
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Correct Answer: C) IBM (International Business Machines)
Explanation: Herman Hollerith founded the Tabulating Machine Company in 1896, which later merged with other firms to become Computing-Tabulating-Recording Company (CTR), renamed IBM in 1924.
3. Which computer classification is built specifically to handle massive volumes of simultaneous transactions for banks, airlines, and census bureaus?
- A) Microcomputer
- B) Workstation
- C) Mainframe Computer
- D) Embedded System
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Correct Answer: C) Mainframe Computer
Explanation: Mainframe computers (such as the IBM zSeries) are engineered for high-volume batch processing and continuous multi-user throughput, whereas supercomputers prioritize raw floating-point calculation speed.
4. A computer designed and hard-coded into dedicated consumer appliances (e.g., microwave ovens, washing machines, car ABS) is an:
- A) Analog Computer
- B) Embedded Computer
- C) Mainframe
- D) Hybrid Computer
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Correct Answer: B) Embedded Computer
Explanation: Embedded systems integrate a dedicated microcontroller or microprocessor with software burned permanently into firmware (ROM) to run specific automated hardware tasks with minimal power and human input.
5. Which early high-level programming language was designed by John Backus at IBM in 1957 primarily for scientific and mathematical calculations?
- A) COBOL
- B) FORTRAN
- C) BASIC
- D) Pascal
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Correct Answer: B) FORTRAN
Explanation: FORTRAN (Formula Translation) was the first commercially successful high-level programming language, optimized for numeric computation and scientific modeling. COBOL was designed for commercial business data.
6. In the CPU instruction processing cycle, what are the four fundamental sequential steps executed in order?
- A) Read, Write, Delete, Save
- B) Fetch, Decode, Execute, Store
- C) Input, Process, Compile, Terminate
- D) Scan, Verify, Print, Log
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Correct Answer: B) Fetch, Decode, Execute, Store
Explanation: Every CPU executes the machine cycle continuously: (1) Fetch the instruction from memory, (2) Decode the binary opcode, (3) Execute the requested arithmetic/logic task, and (4) Store the result back to registers or RAM.
7. What CPU register holds the actual data value or instruction fetched from memory, or ready to be written to memory?
- A) Memory Address Register (MAR)
- B) Memory Data Register (MDR) / Memory Buffer Register (MBR)
- C) Program Counter (PC)
- D) Instruction Pointer
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Correct Answer: B) Memory Data Register (MDR) / Memory Buffer Register (MBR)
Explanation: While the Memory Address Register (MAR) holds the numerical location/address of target memory, the Memory Data Register (MDR) holds the actual contents read from or waiting to be written to that physical address.
8. What is the processing speed of modern supercomputers measured in?
- A) MIPS (Million Instructions Per Second)
- B) FLOPS (Floating-Point Operations Per Second)
- C) MHz (Megahertz)
- D) DPI (Dots Per Inch)
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Correct Answer: B) FLOPS (Floating-Point Operations Per Second)
Explanation: Supercomputers are evaluated based on floating-point performance, designated in TeraFLOPS, PetaFLOPS, and ExaFLOPS ($10^{18}$ calculations/sec). Standard microcomputers are evaluated in MIPS or gigahertz.
9. How many Exabytes (EB) are equal to one Zettabyte (1 ZB) in binary measurement?
- A) 512 EB
- B) 1000 EB
- C) 1024 EB
- D) 2048 EB
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Correct Answer: C) 1024 EB
Explanation: The binary data hierarchy continues beyond Petabytes as follows: $1\text{ Exabyte (EB)} = 1024\text{ PB}$, $1\text{ Zettabyte (ZB)} = 1024\text{ EB}$, and $1\text{ Yottabyte (YB)} = 1024\text{ ZB}$.
10. Which level of CPU Cache memory is usually the fastest, smallest in capacity, and fabricated directly inside each CPU core?
- A) Level 1 (L1) Cache
- B) Level 2 (L2) Cache
- C) Level 3 (L3) Cache
- D) Virtual Cache
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Correct Answer: A) Level 1 (L1) Cache
Explanation: L1 cache runs directly at the core clock speed with zero-wait states. L2 is slightly larger and slower, while L3 is shared across multiple cores and is the largest and slowest of the on-die cache tiers.
11. Which non-impact printer sprays microscopic liquid ink droplets through tiny thermal or piezoelectric print nozzles directly onto the paper?
- A) Daisy Wheel Printer
- B) Inkjet Printer
- C) Dot Matrix Printer
- D) Drum Line Printer
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Correct Answer: B) Inkjet Printer
Explanation: Inkjet printers use cartridges containing liquid ink (cyan, magenta, yellow, black) pushed through hundreds of microscopic nozzles using heat pulses (bubble-jet) or piezoelectric crystals.
12. What optical input device reads parallel black-and-white lines of varying widths printed on consumer retail packaging?
- A) OCR Scanner
- B) Barcode Reader
- C) OMR Reader
- D) Digitizer Puck
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Correct Answer: B) Barcode Reader
Explanation: A barcode scanner uses an optical laser or LED sensor to measure the light reflected back from alternating black bars and white spaces, converting the Universal Product Code (UPC) into digital numerals.
13. What two-dimensional matrix barcode composed of black squares arranged on a white square grid can be decoded rapidly by smartphone cameras?
- A) UPC Barcode
- B) QR (Quick Response) Code
- C) ISBN Code
- D) Postal Stripe
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Correct Answer: B) QR (Quick Response) Code
Explanation: Created by Denso Wave in 1994, QR (Quick Response) codes are 2D matrix symbologies capable of encoding up to several thousand alphanumeric characters, web URLs, and UPI payment strings.
14. What is the dedicated peripheral port designed with 15 pins across three rows traditionally used to connect analog computer monitors to video cards?
- A) DVI
- B) VGA (Video Graphics Array)
- C) DisplayPort
- D) HDMI
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Correct Answer: B) VGA (Video Graphics Array)
Explanation: The blue DE-15 connector standard known as VGA carries analog component video signals (RGB plus horizontal/vertical sync). It has largely been replaced by all-digital HDMI and DisplayPort standards.
15. What type of primary storage memory module allows memory access on both the rising and falling edges of the system clock, doubling data throughput?
- A) SDR-SDRAM
- B) DDR-SDRAM (Double Data Rate)
- C) ROM
- D) Flash ROM
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Correct Answer: B) DDR-SDRAM (Double Data Rate)
Explanation: DDR-SDRAM transfers data on both clock transitions (rising edge and falling edge) per clock cycle, doubling effective bandwidth over legacy Single Data Rate (SDR) SDRAM.
16. What physical circular tracks on optical discs are divided into small microscopic indentations and flat surfaces to represent binary 0s and 1s?
- A) Peaks and Valleys
- B) Pits and Lands
- C) Blocks and Cells
- D) Holes and Marks
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Correct Answer: B) Pits and Lands
Explanation: Optical discs store data by molding microscopic indentations ('Pits') separated by flat reflective areas ('Lands'). An optical laser beam detects the difference in reflection to read binary 0s and 1s.
17. What small round 6-pin mini-DIN ports, color-coded green and purple, were traditionally used on motherboards for mice and keyboards?
- A) USB Ports
- B) PS/2 Ports
- C) Serial COM Ports
- D) FireWire Ports
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Correct Answer: B) PS/2 Ports
Explanation: Introduced with the IBM Personal System/2 in 1987, the PS/2 port used purple for the keyboard and green for the mouse, before being supplanted by plug-and-play USB connectors.
18. What is the main structural chipset component on an older motherboard that controls high-speed communication between the CPU, RAM, and PCIe graphics slots?
- A) Southbridge
- B) Northbridge (Memory Controller Hub)
- C) Super I/O Controller
- D) BIOS ROM
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Correct Answer: B) Northbridge (Memory Controller Hub)
Explanation: In legacy motherboard architecture, the Northbridge managed communications between the processor, RAM, and high-speed AGP/PCIe graphics slots. Slower peripherals (USB, SATA, PCI) were routed through the Southbridge.
19. What software architecture pattern uses a virtual machine to compile source code into an intermediate 'bytecode' executed across multiple operating systems?
- A) Machine Dependent Assembly
- B) Platform Independence (e.g., Java Virtual Machine - JVM)
- C) Direct Microcode Execution
- D) Hardware Abstraction BIOS
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Correct Answer: B) Platform Independence (e.g., Java Virtual Machine - JVM)
Explanation: Platform-independent languages (like Java) compile source code into uniform bytecode (.class), which is interpreted or JIT-compiled at runtime by a platform-specific runtime engine (JVM), fulfilling 'Write Once, Run Anywhere'.
20. What software utility scans for syntax and logic errors in source code and assists developers in stepping through lines to locate software bugs?
- A) Linker
- B) Debugger
- C) Spooler
- D) Text Formatter
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Correct Answer: B) Debugger
Explanation: A debugger allows programmers to set breakpoints, halt execution at specified instructions, inspect register values and variable contents in real time, and trace software flaws.
21. Software that is completely free of copyright restrictions and can be modified, sold, or distributed by anyone without permission is:
- A) Shareware
- B) Public Domain Software
- C) Proprietary Software
- D) Commercial Software
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Correct Answer: B) Public Domain Software
Explanation: Public Domain software has no active copyright, patent, or trademark restrictions. Unlike open-source software with specific licenses (like GPL or MIT), public domain code has no legal restrictions whatsoever.
22. In operating system process scheduling, which scheduling algorithm executes processes strictly in the order they arrive in the ready queue?
- A) Shortest Job First (SJF)
- B) First-Come, First-Served (FCFS)
- C) Round Robin (RR)
- D) Priority Scheduling
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Correct Answer: B) First-Come, First-Served (FCFS)
Explanation: FCFS is a non-preemptive queue scheduling policy where the process that requests the CPU first receives CPU allocation first (FIFO order). It is simple but can suffer from the 'convoy effect'.
23. Which preemptive CPU scheduling algorithm allocates a fixed slice of execution time (quantum) sequentially to each active process?
- A) Round Robin (RR)
- B) FCFS
- C) Shortest Remaining Time First
- D) Static Priority
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Correct Answer: A) Round Robin (RR)
Explanation: Round Robin scheduling is designed for time-sharing systems. Each ready process is granted a short, fixed time quantum (e.g., 10–50 ms). If it does not finish within that period, it is preempted and moved to the back of the queue.
24. In virtual memory management, which page replacement policy replaces the page in memory that has not been accessed for the longest period?
- A) First-In, First-Out (FIFO)
- B) Least Recently Used (LRU)
- C) Most Recently Used (MRU)
- D) Random Replacement
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Correct Answer: B) Least Recently Used (LRU)
Explanation: LRU tracks page usage over time. When a page fault occurs and all RAM frames are full, the OS evicts the page that has gone unreferenced for the longest duration, relying on the principle of temporal locality.
25. What file system structure does Microsoft Windows use by default for internal hard drives and SSDs, offering file permissions and journaling?
- A) FAT16
- B) NTFS (New Technology File System)
- C) ext4
- D) HFS+
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Correct Answer: B) NTFS (New Technology File System)
Explanation: NTFS is the proprietary journaling file system used by default in modern Windows installations. It supports fine-grained access control lists (ACLs), file-level encryption (EFS), disk quotas, and self-healing transaction logs.
26. In modern operating systems, what is a lightweight unit of execution within a process that shares the same address space with other peers called?
- A) Thread
- B) Daemon
- C) Socket
- D) Shell
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Correct Answer: A) Thread
Explanation: A thread is a lightweight sub-process. Multiple threads within the same parent process share code, global memory variables, and open files, but maintain their own independent call stack and program counter.
27. What global Windows shortcut opens the File Explorer file manager window directly?
- A) Windows Key + F
- B) Windows Key + E
- C) Windows Key + R
- D) Windows Key + X
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Correct Answer: B) Windows Key + E
Explanation: Pressing Windows Key + E launches File Explorer (formerly Windows Explorer) to browse drives, directories, and files. Windows Key + R opens the Run dialog box.
28. What is the keyboard shortcut to undo the most recent edit action across almost all Windows applications?
- A) Ctrl + Y
- B) Ctrl + Z
- C) Ctrl + U
- D) Ctrl + X
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Correct Answer: B) Ctrl + Z
Explanation: Ctrl + Z triggers an Undo command, reversing the previous user action. Ctrl + Y re-applies or Redoes the action that was just undone.
29. What is the keyboard shortcut to select all files, text characters, or items within an active document or window?
- A) Ctrl + S
- B) Ctrl + A
- C) Ctrl + All
- D) Shift + A
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Correct Answer: B) Ctrl + A
Explanation: Ctrl + A (Select All) highlights all selectable content across word processing documents, spreadsheets, text fields, or folder listings.
30. In Microsoft Word, which orientation option prints a document wider than it is tall?
- A) Portrait
- B) Landscape
- C) Banner
- D) Panoramic
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Correct Answer: B) Landscape
Explanation: In page layout, Landscape orientation arranges the sheet horizontally ($11 \times 8.5\text{ inches}$ for letter paper). Portrait orientation is the standard vertical layout ($8.5 \times 11\text{ inches}$).
31. What feature in Microsoft Office copies character formatting (font, size, color, borders) from one text block directly to another?
- A) AutoCorrect
- B) Format Painter
- C) Style Master
- D) Clipboard Paste
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Correct Answer: B) Format Painter
Explanation: The Format Painter tool (paintbrush icon on the Home tab) copies all visual styling attributes from selected text and applies them to other content with a click.
32. In Microsoft Word, what is a note placed at the very end of an entire document rather than at the bottom of the current page called?
- A) Footnote
- B) Endnote
- C) Footer
- D) Caption
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Correct Answer: B) Endnote
Explanation: Footnotes appear at the bottom of the specific page containing the citation reference mark. Endnotes appear collected together at the very end of the document or section.
33. In Microsoft Excel, what keyboard shortcut toggles an absolute, mixed, and relative reference on a selected cell address inside a formula?
- A) F2
- B) F4
- C) F9
- D) F12
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Correct Answer: B) F4
Explanation: While editing an Excel formula, placing the cursor next to a reference like 'A1' and pressing F4 cycles through absolute ($A$1), mixed row ($A1), mixed column (A$1), and relative (A1) states.
34. In Microsoft Excel, what function counts only those cells within a specified range that satisfy a given conditional rule?
- A) COUNT()
- B) COUNTA()
- C) COUNTIF()
- D) SUMIF()
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Correct Answer: C) COUNTIF()
Explanation: COUNTIF counts the number of cells matching a specific criteria (e.g., =COUNTIF(A1:A10, ">50")). COUNTA counts all non-empty cells regardless of content.
35. In Microsoft PowerPoint, which keyboard key stops and exits an ongoing slide show immediately, returning to normal editing view?
- A) Enter
- B) Spacebar
- C) Escape (Esc)
- D) Backspace
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Correct Answer: C) Escape (Esc)
Explanation: Pressing the Escape (Esc) key during an active presentation immediately exits the full-screen slide show mode and returns to PowerPoint's editing interface.
36. Which networking topology connects every computer node directly to every other computer node with dedicated point-to-point physical links?
- A) Star Topology
- B) Ring Topology
- C) Mesh Topology
- D) Bus Topology
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Correct Answer: C) Mesh Topology
Explanation: In a full mesh topology, every device has a dedicated physical connection to every other device in the network. While expensive due to cabling, it provides high fault tolerance with no single point of failure.
37. What is the networking standard that specifies collision detection protocols for carrier-sense local area networks (CSMA/CD)?
- A) IEEE 802.3 (Ethernet)
- B) IEEE 802.11 (Wi-Fi)
- C) IEEE 802.15 (Bluetooth)
- D) IEEE 802.16 (WiMAX)
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Correct Answer: A) IEEE 802.3 (Ethernet)
Explanation: IEEE 802.3 defines physical and data-link specifications for wired Ethernet networks, historically utilizing Carrier Sense Multiple Access with Collision Detection (CSMA/CD).
38. What is the international standard designation for wireless local area networking (Wi-Fi)?
- A) IEEE 802.2
- B) IEEE 802.3
- C) IEEE 802.11
- D) IEEE 802.15
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Correct Answer: C) IEEE 802.11
Explanation: The IEEE 802.11 family of specifications governs Wireless Local Area Networks (WLANs), commonly marketed as Wi-Fi across frequencies like 2.4 GHz, 5 GHz, and 6 GHz.
39. What networking device connects two distinct local area network segments operating on the same protocol at the Data Link Layer (Layer 2)?
- A) Repeater
- B) Network Bridge
- C) Gateway
- D) Modem
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Correct Answer: B) Network Bridge
Explanation: A Bridge connects two separate physical segments of a single logical network at Layer 2 (Data Link), filtering or forwarding traffic between them based on destination MAC addresses to reduce local traffic congestion.
40. What protocol translates a private local IP address (like 192.168.1.10) into a public routable IP address for internet communication?
- A) DHCP
- B) NAT (Network Address Translation)
- C) DNS
- D) RIP
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Correct Answer: B) NAT (Network Address Translation)
Explanation: NAT (Network Address Translation), implemented on edge routers and firewalls, maps multiple private, non-routable local IPv4 addresses to a single public IP address, conserving IPv4 space.
41. In the OSI reference model, which layer handles data compression, format translations (ASCII, JPEG), and data encryption/decryption?
- A) Transport Layer
- B) Session Layer
- C) Presentation Layer (Layer 6)
- D) Application Layer
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Correct Answer: C) Presentation Layer (Layer 6)
Explanation: The Presentation Layer is responsible for syntax translation, character encoding conversions, data compression, and cryptographic encryption/decryption to prepare data for the Application Layer.
42. What network protocol is an unencrypted, connectionless alternative to TCP that prioritizes low-latency transmission over packet reliability?
- A) UDP (User Datagram Protocol)
- B) FTP
- C) ICMP
- D) ARP
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Correct Answer: A) UDP (User Datagram Protocol)
Explanation: UDP is a lightweight, connectionless Transport Layer protocol that does not establish handshakes, track sequence order, or resend lost packets, making it suitable for live video streaming, voice calls, and gaming.
43. What is the default loopback IP address assigned to every local computer to test its internal TCP/IP network stack?
- A) 192.168.0.1
- B) 127.0.0.1
- C) 10.0.0.1
- D) 255.255.255.0
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Correct Answer: B) 127.0.0.1
Explanation: The IPv4 loopback address 127.0.0.1 (referred to as 'localhost') routes outgoing network packets directly back to the host machine without traversing external physical network interfaces.
44. What is a private, restricted enterprise computer network accessible only to internal organization employees called?
- A) Internet
- B) Intranet
- C) Extranet
- D) Ethernet
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Correct Answer: B) Intranet
Explanation: An Intranet is a private internal network that uses internet protocols (HTTP, TCP/IP) protected behind corporate firewalls to share organizational information, internal portals, and operational tools exclusively with authorized staff.
45. What type of computer virus infects the primary Master Boot Record (MBR) or partition table of a physical storage drive?
- A) Macro Virus
- B) Boot Sector Virus
- C) File Infector Virus
- D) Polymorphic Virus
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Correct Answer: B) Boot Sector Virus
Explanation: A Boot Sector virus replaces or infects the Master Boot Record (MBR) on a hard drive or USB drive, executing malicious instructions into memory before the operating system even begins loading.
46. What form of social engineering uses fraudulent telephone voice calls or automated voice messages to deceive victims into revealing financial data?
- A) Smishing
- B) Vishing (Voice Phishing)
- C) Pharming
- D) Spoofing
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Correct Answer: B) Vishing (Voice Phishing)
Explanation: Vishing (voice phishing) uses phone calls or voice-over-IP spoofing to impersonate banks or government agencies to obtain account details or OTPs. Fraudulent SMS messaging is known as Smishing.
47. What cryptographic system uses a pair of mathematical keys (a Public Key for encryption and a Private Key for decryption)?
- A) Symmetric Key Cryptography
- B) Asymmetric Key Cryptography (Public-Key Cryptography)
- C) Stream Cipher
- D) Block Cipher
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Correct Answer: B) Asymmetric Key Cryptography (Public-Key Cryptography)
Explanation: Asymmetric cryptography (such as RSA or ECC) uses two mathematically linked keys: a public key shared openly to encrypt messages, and a secret private key kept by the recipient to decrypt them.
48. What is a mathematical scheme used to verify the authenticity, integrity, and non-repudiation of a digital document or software message called?
- A) Digital Watermark
- B) Digital Signature
- C) Hash Table
- D) Passkey
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Correct Answer: B) Digital Signature
Explanation: A digital signature binds a sender's identity to a message using asymmetric cryptography and cryptographic hash digests, ensuring the content has not been tampered with in transit.
49. What is a secret hardware or software flaw introduced intentionally or accidentally that bypasses normal security access controls called?
- A) Firewall
- B) Backdoor (Trapdoor)
- C) Proxy
- D) Router
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Correct Answer: B) Backdoor (Trapdoor)
Explanation: A Backdoor allows remote access to a system while bypassing standard authentication mechanisms, often installed by malware (Trojans) or planted by developers for hidden access.
50. In relational database systems (RDBMS), an attribute or column in one table that links to and references the Primary Key of another table is a:
- A) Candidate Key
- B) Foreign Key
- C) Composite Key
- D) Alternate Key
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Correct Answer: B) Foreign Key
Explanation: A Foreign Key is a field in a relational database table that points to the primary key column in a related parent table, enforcing referential integrity across the database model.