Basic computer operations (hardware and software)

A power supply unit must provide stable voltage and sufficient current to the computer’s components. When demand rises during gaming, intensive calculation, or another heavy workload, an undersized or failing unit may trigger voltage protection, causing an unexpected shutdown or restart. Option C is correct. The other options are unrelated to power delivery.

A traditional hard disk drive stores data on rotating magnetic platters. To read a requested block, its actuator must move the read/write head to the correct track, and the platter must rotate until the desired sector arrives. These seek and rotational-latency movements create mechanical delay. Therefore, option A is correct; the other choices do not affect disk positioning.

The governing concept is effective storage management. An operating system uses free disk space for temporary files, updates, caches, and virtual memory when RAM is insufficient. If the drive is nearly full, these operations become constrained, so applications may open or respond slowly. Option C is correct; printer ink, monitor colour, and mouse input do not normally depend on remaining storage space.

Safe Mode starts the computer with only essential drivers and services. If the fault disappears there but returns in normal mode, a driver, startup program, or optional service is a likely cause. Therefore, option A is correct. The other choices do not follow from this comparison: a faulty monitor would usually affect both modes, and RAM or hard-disk facts are unrelated to the diagnostic result.

A System Restore point records important system settings, drivers, and configuration information at a particular time. Creating one before installing a major driver or software change provides a recovery option if the change causes instability. Thus, option B is correct. It generally does not replace a personal-data backup, and the other events do not normally create a useful system-recovery checkpoint.

A full backup copies every selected file and folder, so restoring from that single backup is usually straightforward but requires more storage and time. An incremental backup copies only data changed since the immediately preceding backup, saving space and time while making recovery dependent on the required backup sequence. Therefore, option C is correct; A and B reverse the definitions.

Lossless compression reduces file size by representing repeated or predictable information more efficiently, while preserving every original bit for exact decompression. Lossy compression achieves greater reduction by discarding details judged less important, so the original cannot be reconstructed perfectly. Option B states this distinction. The other choices either reverse the definitions or make unjustified claims about size and file type.

An executable file contains exact instructions and data that the operating system must interpret correctly. Removing or changing even a small portion can make the program fail or behave unpredictably, so lossless compression is required. Option C is correct. Audio, video, and social-media images may sometimes tolerate controlled quality loss, depending on their purpose, although lossless formats can also be chosen for them.

Quarantine is a protective function of security software. It moves a suspected malicious file to a restricted location or changes its access so the file cannot execute normally or interact with other data. This gives the user or security tool time to analyse, delete, or restore it safely. Option A is correct; sending the file, removing antivirus, or formatting the system is not the purpose of quarantine.

The governing concept is permission-based privacy and least-privilege access. An application should receive only the device access necessary for its stated function. A camera or microphone request without a clear need can expose private images, sound, or conversations. Therefore, option C is correct: deny the request first and verify the developer, source, reviews, and privacy policy. Granting everything is unsafe, while removing the operating system or formatting a drive is unrelated and unnecessarily destructive.

The governing concept is software authenticity and secure installation. Official websites or trusted app stores are more likely to distribute the developer’s genuine, current package and provide update information. This reduces, although it does not completely eliminate, the chance of malware, tampering, or an unsafe modified installer. Option D is correct. Official sources do not improve screen colors, guarantee free storage, or remove passwords, so A, B, and C are unrelated claims.

The governing concept is operating-system scheduling. The scheduler decides which ready process receives CPU time, and a higher priority can make a process more likely to be selected sooner or more often, depending on the scheduling policy. Thus option A is correct, but it does not create extra storage or change physical hardware. Giving one process preference can also delay lower-priority tasks, so priorities should be changed carefully.

The governing concept is safe process management and graceful shutdown. A program should normally be closed through its own command so it can save files and release resources correctly. If it remains unresponsive for a long time and cannot close normally, force-ending it through a task manager may be appropriate as a last resort. Therefore B is correct. Unsaved work can be lost; the printer and screen conditions do not justify termination.

The governing concept is memory management. When software obtains memory for data but fails to return it after the data or application is no longer using it, the retained allocation is called a memory leak. Repeated leaks can gradually reduce available memory, cause slow performance, or make applications unstable. Option C is correct. Disk partitioning divides storage, secure boot checks startup software, and file compression reduces file size; none describes unreleased memory.

The governing concept is system-failure diagnosis. A repeated blue error screen generally indicates that the operating system has detected a serious problem from which it cannot safely continue. Possible causes include an incompatible or faulty driver, defective hardware, damaged system files, or other system faults. Option D is correct, although the exact cause requires evidence and diagnostic checks. A long filename, clean monitor, or fresh printer paper does not normally produce this type of failure.

The governing concept is evidence-based troubleshooting. Recording when the problem occurs, exact error messages, frequency, and recent changes creates a useful timeline. A technician can compare that evidence with possible causes, reproduce the fault, and test one explanation at a time instead of guessing. Therefore option A is correct. Recording symptoms does not increase CPU speed, clean storage automatically, or refill printer ink; those claims are unrelated to diagnosis.

The governing concept is substitution testing and fault isolation. If a known working device is connected to the same computer and works correctly, suspicion shifts toward the original device, cable, or connection. If the replacement also fails, the computer, port, or software may be responsible. Thus option B is correct. This method does not delete files, reinstall the operating system, or change monitor brightness. Testing one variable at a time makes the conclusion more reliable.

The governing concept is change-based troubleshooting: a recent change is a strong clue about causation. The first checks should confirm that the new hardware is supported by the computer, firmly connected, correctly installed, and using a compatible driver. Therefore option D is correct. Deleting personal files or replacing the operating system is excessive and may cause data loss, while adding printer paper is unrelated. If needed, safely removing the new device can further test the diagnosis.

The governing concept is electrostatic discharge (ESD): a small static charge from the body can pass into an electronic circuit and damage delicate components. Grounding yourself before touching parts safely releases or equalizes that charge. Therefore, option A is correct. Wet hands create a shock and corrosion risk, removing parts while powered can cause electrical damage, and rubbing memory on metal can create harmful discharge.

Final verification is the troubleshooting step in which the original task is repeated under similar conditions to confirm that the proposed solution really worked. Stable operation, correct results, and the safety or integrity of important data should also be checked. Thus option B is correct. Erasing an error message does not prove resolution, while stopping updates or deleting a backup can reduce security and recovery options.

The correct answer is A. During startup, the firmware first performs a power-on self-test to check essential hardware. After a successful test, it locates a bootable device and loads the operating-system boot loader, or the initial loading code, into main memory. That code then helps load the operating system. Compressing files, removing drivers, or setting brightness to zero is not a normal next boot stage.

The governing concept is a cache hit in the memory hierarchy. The processor first checks the small, fast cache for recently or frequently used data. If the required data is present, it can use that copy instead of requesting it from slower main memory, so access time and waiting are reduced. Option B is correct; the other options concern storage capacity, display quality, or security, none of which is directly changed by a cache hit.

The governing concept is interrupt-driven processing. An interrupt is a signal from hardware or software telling the processor that an event needs service, such as input arrival, a timer event, or an I/O operation finishing. The processor can pause its current work, run the appropriate service routine, and then continue. Option A is correct. The other choices describe neither notification nor processor event handling.

The governing concept is driver compatibility. A device driver translates operating-system commands into instructions the hardware understands. If the driver does not support the new operating-system version, communication may fail, so the device can work incorrectly, lose features, show errors, or remain undetected. Option B is correct. An incompatible driver does not automatically alter storage capacity, delete accounts, or transform one device into another.

The governing concept is language translation in system software. A compiler translates a complete source program into machine or object code, while an interpreter translates and executes instructions step by step. Both are language translators, so option D is the suitable general answer. A file manager handles files, antivirus detects threats, and a device driver controls communication with specific hardware.