D684 Introduction to Computer Science - Set 4 - Part 2

Correct Answer: Hardware entropy

Hardware entropy derives randomness from physical phenomena like electrical noise, providing unpredictable values for secure key generation.
Option a is incorrect because timestamp values follow predictable patterns that attackers could potentially reproduce or guess.
Option c is incorrect because sequential numbers are completely predictable, providing no security for private key generation.
Option d is incorrect because algorithm output is deterministic and reproducible, lacking the true randomness for secure keys.

Correct Answer: Adaptive bitrate

Adaptive bitrate streaming adjusts quality dynamically based on network conditions, preventing interruptions while maximizing available quality.
Option a is incorrect because fixed bitrate cannot adapt to network changes, causing buffering when bandwidth drops below requirements.
Option c is incorrect because maximum quality requires high bandwidth consistently, causing interruptions when networks slow down temporarily.
Option d is incorrect because minimum quality wastes available bandwidth and provides poor experience when networks could support better.

Correct Answer: Real-time processing

Real-time processing analyzes images immediately as products pass, enabling instant defect detection on fast-moving conveyor belts.
Option b is incorrect because batch processing accumulates images before analysis, missing defects until after products pass inspection points.
Option c is incorrect because manual processing is too slow for fast conveyor belts and prone to human error and fatigue.
Option d is incorrect because delayed processing allows defective products to continue through production before detection occurs.

Correct Answer: Consensus protocol

Consensus protocols enable distributed nodes to agree on transaction order without central control, maintaining ledger consistency across networks.
Option a is incorrect because central voting requires a central authority, contradicting the distributed nature of the ledger system.
Option c is incorrect because random selection doesn't ensure all nodes agree on transaction order, causing ledger inconsistencies.
Option d is incorrect because manual approval is too slow and requires human intervention, defeating distributed automation purposes.

Correct Answer: Processing speed

Processing speed enables checking thousands of passengers without creating delays, critical for maintaining airport traffic flow efficiently.
Option a is incorrect because perfect accuracy is impossible and pursuing it would slow processing below acceptable airport throughput.
Option c is incorrect because storage capacity affects database size but doesn't directly impact real-time passenger processing speed.
Option d is incorrect because network bandwidth affects data transfer but local processing speed determines passenger throughput rates.

Correct Answer: Online learning

Online learning continuously updates from user input, personalizing autocorrect to individual vocabulary and typing patterns over time.
Option a is incorrect because static dictionaries cannot adapt to user-specific words or personal typing patterns and preferences.
Option c is incorrect because batch learning requires collecting data before learning, not continuously adapting to user patterns.
Option d is incorrect because transfer learning applies pre-trained models but doesn't personalize to specific user typing habits.

Correct Answer: Signal filtering

Signal filtering removes noise and clutter based on characteristics like movement patterns, distinguishing real aircraft from false signals.
Option b is incorrect because signal amplification increases all signals including clutter, making aircraft harder to distinguish from noise.
Option c is incorrect because signal compression reduces data size but doesn't help distinguish aircraft from weather or clutter.
Option d is incorrect because signal duplication creates copies but doesn't separate real targets from false radar returns.

Correct Answer: Three-way merge

Three-way merge compares changes against common ancestors, intelligently combining modifications and identifying conflicts requiring human resolution.
Option b is incorrect because binary merge only handles two versions without considering common ancestry, losing important context information.
Option c is incorrect because sequential merge applies changes in order, potentially overwriting earlier valid modifications from other developers.
Option d is incorrect because random merge would arbitrarily choose changes, creating inconsistent and potentially broken code results.

Correct Answer: Optimization algorithm

Optimization algorithms calculate efficient routes considering all pending requests, minimizing total wait time across all passengers.
Option a is incorrect because first-come-first-served ignores efficiency, causing excessive travel and longer overall wait times.
Option b is incorrect because nearest floor first might ignore clusters of waiting passengers, increasing total wait time.
Option d is incorrect because random selection produces inefficient routes, maximizing rather than minimizing passenger wait times.

Correct Answer: Distributed hashing

Distributed hashing creates verifiable file fingerprints shared across peers, enabling authentication without central authority or servers required.
Option a is incorrect because central certification requires servers that peer-to-peer networks specifically aim to avoid for decentralization.
Option c is incorrect because manual verification is impractical for large files and numerous peers in sharing networks.
Option d is incorrect because trust assumption provides no actual verification, allowing corrupted or malicious files to spread.

Correct Answer: Feedback control

Feedback control continuously adjusts telescope position based on object location, compensating for Earth's rotation during extended observations.
Option a is incorrect because manual adjustment requires constant human intervention, impractical for hours-long astronomical observations requiring precision.
Option c is incorrect because open control cannot correct for tracking errors that accumulate over time without feedback.
Option d is incorrect because random movement would lose celestial objects entirely, making astronomical observation impossible.

Correct Answer: Rotation detection

Rotation detection identifies skew angles in scanned documents, enabling automatic correction before text extraction for better accuracy.
Option a is incorrect because color correction improves appearance but doesn't fix skewed text that causes recognition errors.
Option c is incorrect because contrast adjustment enhances readability but doesn't correct angular skew in scanned documents.
Option d is incorrect because resolution enhancement improves detail but doesn't address skewed orientation affecting text recognition.

Correct Answer: Deterministic generation

Deterministic generation uses seed values to create identical worlds from same inputs, ensuring locations remain consistent across visits.
Option a is incorrect because random generation creates different worlds each time, destroying consistency when players revisit locations.
Option c is incorrect because manual creation cannot produce infinite worlds, limiting game exploration to pre-built areas only.
Option d is incorrect because template copying creates repetitive patterns players recognize, breaking immersion in supposedly infinite worlds.

Correct Answer: Flow analysis

Flow analysis traces possible execution paths through code, identifying unreachable statements that follow unconditional returns or exits.
Option b is incorrect because type analysis verifies data type compatibility but doesn't determine which code paths are reachable.
Option c is incorrect because memory analysis tracks allocation and deallocation, not identifying unreachable code sections in programs.
Option d is incorrect because performance analysis measures execution efficiency, not detecting code that will never execute.

Correct Answer: Predictive analytics

Predictive analytics identifies patterns indicating learning difficulties early, enabling intervention before students fail important assessments or courses.
Option a is incorrect because descriptive analytics summarizes past performance but doesn't predict future struggles requiring intervention.
Option c is incorrect because random analytics would provide no meaningful insights about student learning patterns or difficulties.
Option d is incorrect because historical analytics examines past data but doesn't predict current students' future performance issues.

Correct Answer: Quality of service

Quality of service assigns priority levels to different traffic types, ensuring emergency communications transmit despite network congestion.
Option a is incorrect because equal access treats all traffic identically, potentially blocking critical emergency communications during disasters.
Option c is incorrect because random access provides unpredictable service, unacceptable for emergency services requiring guaranteed communication.
Option d is incorrect because delayed access would postpone emergency communications, potentially causing loss of life during disasters.

Correct Answer: Resource profiling

Resource profiling tracks CPU, network, and sensor usage by apps, identifying which consume excessive battery in background operation.
Option a is incorrect because screen monitoring only tracks display usage, missing background app activity draining battery power.
Option b is incorrect because network monitoring only captures data usage, not complete picture of battery consumption patterns.
Option d is incorrect because user monitoring tracks interactions but misses autonomous background activities draining battery resources.

Correct Answer: Proof of work

Proof of work requires massive computational effort to rewrite history, making attacks economically infeasible even with significant resources.
Option a is incorrect because encryption protects data confidentiality but doesn't prevent computational attacks on blockchain history integrity.
Option c is incorrect because access control restricts users but doesn't prevent authorized miners from attempting history rewrites.
Option d is incorrect because data compression reduces storage size but provides no security against transaction history manipulation.

Correct Answer: Trapezoidal motion

Trapezoidal motion profiles include acceleration, constant velocity, and deceleration phases, minimizing mechanical stress on robotic components.
Option a is incorrect because linear motion maintains constant speed without acceleration phases, causing jerky starts and stops.
Option c is incorrect because random motion creates unpredictable forces, potentially damaging mechanical components through sudden changes.
Option d is incorrect because stepped motion creates discrete jumps, causing mechanical shock and wear on robotic joints.

Correct Answer: Exploration-exploitation tradeoff

Exploration-exploitation tradeoff balances showing content similar to user preferences while introducing new content for discovery and engagement.
Option a is incorrect because pure exploitation only suggests familiar content, causing user boredom and missing potential new interests.
Option b is incorrect because pure exploration ignores user preferences, suggesting irrelevant content that reduces engagement and satisfaction.
Option d is incorrect because random selection disregards both preferences and discovery strategy, providing poor user experience overall.