151. Which one of the following is not an operating system?

Which one of the following is not an operating system?

[amp_mcq option1=”MS-Windows” option2=”Linux” option3=”Ubuntu” option4=”MS-Excel” correct=”option4″]

This question was previously asked in
UPSC CAPF – 2022
An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. MS-Windows, Linux, and Ubuntu are all examples of widely used operating systems. MS-Excel, on the other hand, is an application software, specifically a spreadsheet program, used for data analysis, calculations, and visualization. It runs *on* an operating system.
The question asks to identify which option is *not* an operating system. Operating systems are fundamental software that allows other programs to run and manage hardware, while application software performs specific user tasks.
Examples of operating systems include Microsoft Windows, macOS, Linux, Android, and iOS. Examples of application software include word processors (like MS Word), web browsers (like Chrome, Firefox), email clients, media players, games, and spreadsheet programs (like MS-Excel).

152. Which one of the following portals was launched on the 250th anniversa

Which one of the following portals was launched on the 250th anniversary of Survey of India ?

[amp_mcq option1=”ServicePlus” option2=”DigiMap” option3=”Udaan” option4=”Nakshc” correct=”option4″]

This question was previously asked in
UPSC CAPF – 2017
The Survey of India, established in 1767, celebrated its 250th anniversary in 2017. On this occasion, the government launched the ‘Nakshc’ (or Nakshe) portal, providing free public access to digitized topographical maps (open series maps) of the country for download.
The ‘Nakshc’ portal was launched by the Survey of India in 2017 to provide public access to maps.
The Nakshe portal (nakshe.surveyofindia.gov.in) allows users to download maps in PDF format, subject to terms and conditions. This initiative was part of the government’s efforts to promote geospatial data availability and use.

153. What is clickjacking ?

What is clickjacking ?

[amp_mcq option1=”A device that sends and receives data at every click in a bit second” option2=”A device which does/counts clicks on internet” option3=”A malicious technique of tricking Web users into revealing confidential information” option4=”A digital process that is used to display an image on mobiles” correct=”option3″]

This question was previously asked in
UPSC CAPF – 2014
Clickjacking is a malicious technique used on the web to trick users into performing actions they did not intend, often leading to the revelation of confidential information or unauthorized actions.
This is achieved by layering a transparent or opaque iframe containing a malicious page over a legitimate web page. Users are lured to click on what appears to be a benign element on the visible page (e.g., a button), but their click is actually registered by the hidden malicious layer. This allows attackers to hijack clicks, making users unknowingly click on buttons or links that execute harmful actions, such as transferring money, changing passwords, or revealing sensitive data.
Clickjacking is also known as a “UI redress attack”. Websites can protect against clickjacking using techniques like X-Frame-Options HTTP headers (like DENY or SAMEORIGIN) or JavaScript-based frame-breaking code.

154. Nowadays a new term ‘jail breaking’ is in use. It implies a process :

Nowadays a new term ‘jail breaking’ is in use. It implies a process :

[amp_mcq option1=”of running away from most secured jails of USA by hardcore criminals” option2=”that gives users the ability to install unauthorized software on certain types of phones” option3=”of breaking security system by hackers using WiMAX technology” option4=”of hacking authorized software from computers, laptop and mobiles” correct=”option2″]

This question was previously asked in
UPSC CAPF – 2014
‘Jail breaking’ refers to the process of modifying the operating system of certain mobile phones (specifically Apple’s iOS devices like iPhones and iPads) to remove restrictions imposed by the manufacturer.
This process allows users to gain full access to the root of the operating system and install software from unofficial sources, customize the interface beyond standard options, and change system settings that are normally locked. It essentially liberates the device from the constraints of the official software ecosystem.
While jailbreaking allows greater control and flexibility, it also carries risks, including potentially voiding the warranty, making the device less secure against malware and vulnerabilities, and causing instability or performance issues. A similar process for Android devices is called ‘rooting’.

155. 3G and 4G are wireless technologies, which are supposedly faster, more

3G and 4G are wireless technologies, which are supposedly faster, more secure and reliable. Present day 3G technology is capable of handling data around 2 Megabits per second (1.8 – 2.5 GHz frequency band). What speed is expected from new 4G technology ?

[amp_mcq option1=”10-30 Megabits per second (1-5 GHz frequency band)” option2=”10-100 Megabits per second (2-10 GHz frequency band)” option3=”100 Megabits—1 Gigabit per second (2-8 GHz frequency band)” option4=”More than 10 Gigabits per second (10-20 GHz frequency band)” correct=”option3″]

This question was previously asked in
UPSC CAPF – 2014
The correct answer is 100 Megabits—1 Gigabit per second (2-8 GHz frequency band).
The question asks about the expected speed from new 4G technology compared to 3G (around 2 Mbps). 4G, specifically LTE (Long-Term Evolution), was designed to provide significantly higher data rates. While real-world speeds vary greatly depending on network conditions and load, the theoretical peak speeds and design targets for 4G are much higher than 3G.
LTE (4G) typically aims for peak downlink speeds of 100 Mbps for high-mobility users and up to 1 Gbps for low-mobility users (in advanced versions like LTE-Advanced). Peak uplink speeds are lower, typically up to 50 Mbps.
Comparing the options:
A) 10-30 Mbps: Only slightly better than 3G, too low for 4G targets.
B) 10-100 Mbps: Covers the lower end of 4G peak downlink but doesn’t capture the higher potential.
C) 100 Megabits—1 Gigabit per second: This range accurately reflects the peak theoretical speeds achievable by 4G and LTE-Advanced technologies, particularly the upper bound in ideal conditions.
D) More than 10 Gigabits per second: This speed range is characteristic of 5G technology, not 4G.
The frequency band mentioned (2-8 GHz) is also plausible for 4G deployments, although 4G uses various bands depending on the region and spectrum availability.
4G represents a significant leap in mobile communication speeds compared to 3G, enabling services like HD video streaming and faster internet access. While 1 Gbps was an ambitious target often associated with theoretical peaks or LTE-Advanced Pro, the range of 100 Mbps to 1 Gbps captures the intended performance increase over 3G.

156. Which of the following is the correct chronological order of TV displa

Which of the following is the correct chronological order of TV display technologies?

[amp_mcq option1=”CRT, Plasma, LED” option2=”CRT, LED, Plasma” option3=”LED, CRT, Plasma” option4=”Plasma, LED, CRT” correct=”option1″]

This question was previously asked in
UPSC CAPF – 2013
The correct option is A.
– The question asks for the correct chronological order of the introduction and prevalence of different TV display technologies.
– **CRT (Cathode Ray Tube):** This was the dominant technology for televisions and computer monitors for many decades, from the mid-20th century until the early 2000s. It is the oldest among the options.
– **Plasma Display Panel (PDP):** Plasma technology emerged as a competitor to CRTs and early LCDs in the late 1990s and became popular for large-screen televisions in the early to mid-2000s.
– **LED (Light Emitting Diode):** In the context of televisions replacing older technologies, LED typically refers to LCD TVs that use LED backlighting instead of traditional fluorescent (CCFL) backlighting. These “LED TVs” became widely available and popular in the late 2000s, offering better contrast, thinner profiles, and energy efficiency compared to CCFL-backlit LCDs and Plasma displays, eventually replacing both in the mass market. (True self-emissive LED displays like MicroLED are newer).
– The chronological order of mass-market prevalence is therefore CRT, followed by Plasma (and early LCDs), followed by LED-backlit LCDs (often just marketed as “LED TVs”).
LCD (Liquid Crystal Display) technology also emerged alongside Plasma as a flat-panel alternative to CRT and eventually surpassed both. Early LCDs used CCFL backlights. The term “LED TV” refers to LCD TVs with LED backlighting. So, the broader progression was CRT -> Plasma/LCD (CCFL) -> LCD (LED). The option provides LED as a distinct category following Plasma, which is accurate in terms of market adoption waves.

157. Which one among the following statements about ‘modem’ is correct?

Which one among the following statements about ‘modem’ is correct?

[amp_mcq option1=”Modem is a software” option2=”Modem helps in stabilizing the voltage” option3=”Modem is an operating system” option4=”Modem converts the analog signal into digital signal and vice versa” correct=”option4″]

This question was previously asked in
UPSC CAPF – 2013
D) Modem converts the analog signal into digital signal and vice versa
A modem, which stands for Modulator-Demodulator, is a networking hardware device. Its primary function is to convert digital signals generated by a computer or other digital device into analog signals that can be transmitted over traditional analog communication channels like telephone lines or coaxial cables (modulation). Conversely, it receives incoming analog signals from the communication line and converts them back into digital signals that the computer can understand (demodulation). This process allows digital devices to communicate over analog infrastructure.
Modems are essential for many types of internet connections, including dial-up, DSL, and cable internet. They bridge the gap between the digital world of computers and the analog nature of certain transmission media. While modern networks often use digital signals end-to-end, modems are still necessary at the interface with older or specific transmission technologies.

158. Electricity meter may be a/an

Electricity meter may be a/an

[amp_mcq option1=”mainframe computer” option2=”microcomputer” option3=”hybrid computer” option4=”analog computer” correct=”option4″]

This question was previously asked in
UPSC CAPF – 2013
The correct option is D. An electricity meter may be an analog computer.
Traditional electromechanical electricity meters, commonly used for many years, are essentially analog devices. They measure instantaneous power (voltage multiplied by current) and integrate it over time to calculate the total energy consumed. This process of integrating a continuously varying signal (power) over time is a form of analog computation, where a physical quantity (like the rotation of a disk) represents the cumulative energy. While modern smart meters are digital and incorporate microcomputers, the question likely refers to the fundamental nature or a common type of electricity meter as a device that processes continuous electrical signals to compute energy.
Mainframe, microcomputer, and hybrid computers are classifications of general-purpose computing systems. While modern digital electricity meters contain embedded microcomputers, the *function* of measuring and integrating energy consumption, especially in older meter types, aligns with the principles of analog computation where continuous variables are processed.

159. ‘Turing machine’ serves as

‘Turing machine’ serves as

[amp_mcq option1=”a machine to identify explosives” option2=”an indicator to inform about forest fire” option3=”an instrument for finding out gravitational constant” option4=”a theoretical computing machine to act as an ideal model for mathematical calculation” correct=”option4″]

This question was previously asked in
UPSC CAPF – 2013
The correct option is D. A Turing machine is a theoretical computing machine that serves as an ideal model for mathematical calculation.
Proposed by Alan Turing in 1936, the Turing machine is a mathematical model of computation. It defines an abstract machine that manipulates symbols on a strip of tape according to a set of rules. It is used to study the limits of computation and the concepts of algorithms and computability. It is not a physical machine designed for practical tasks like identifying explosives or measuring constants.
The Church-Turing thesis states that any algorithmic process can be simulated by a Turing machine. This makes the Turing machine a fundamental concept in computer science and the theory of computation. Modern computers are often described as being Turing-complete, meaning they can perform any computation that a universal Turing machine can.

160. Wi-Fi in a computer implies

Wi-Fi in a computer implies

[amp_mcq option1=”wired local area network” option2=”wireless local area network” option3=”high fidelity” option4=”high efficiency” correct=”option2″]

This question was previously asked in
UPSC CAPF – 2012
Wi-Fi is a technology that enables wireless communication within a local area network (LAN). It is based on the IEEE 802.11 family of standards.
– Wi-Fi stands for Wireless Fidelity (though this is not a formally recognized term by the Wi-Fi Alliance).
– It creates a Wireless Local Area Network (WLAN).
– Used for connecting devices to a network wirelessly over short to medium distances.
Wi-Fi is the most common technology used for accessing the internet wirelessly in homes, offices, and public spaces. It operates on radio waves, typically in the 2.4 GHz and 5 GHz frequency bands.