D686 Operating Systems for Computer Scientists - Set 4 - Part 3

Correct Answer: Exclusive locking

Exclusive locking grants edit permission to one user while others can view, preventing conflicting modifications while maintaining document visibility for collaboration awareness effectively coordinated systematically throughout sessions.
Option a is incorrect because no locking allows simultaneous edits creating conflicts when multiple users modify the same content causing data loss and confusion potentially occurring.
Option c is incorrect because shared viewing without edit control doesn't address the need for controlled modification; collaboration needs managed not unrestricted editing for consistency fundamentally required.
Option d is incorrect because free editing creates chaos with conflicting changes; document integrity requires controlled not unlimited modification access for maintaining consistency throughout collaboration effectively.

Correct Answer: Distributed ledger

Distributed ledger technology creates tamper-proof custody records across supply chain participants, ensuring accountability and traceability that centralized systems cannot guarantee effectively throughout logistics operations comprehensively maintained.
Option a is incorrect because local databases can be modified destroying audit trails; supply chains need immutable not editable records for trust and accountability fundamentally required absolutely.
Option c is incorrect because spreadsheet tracking lacks security and audit features; logistics needs cryptographically secured not manually maintained records for reliability and trust essentially necessary.
Option d is incorrect because paper records are easily forged or lost; modern supply chains need digital immutable records not physical documents for accountability required practically.

Correct Answer: Privacy-preserving aggregation

Privacy-preserving aggregation computes utility statistics without exposing individual consumption patterns, balancing infrastructure monitoring needs with citizen privacy rights through cryptographic techniques implemented systematically throughout collection processes.
Option a is incorrect because raw collection exposes individual usage patterns violating privacy; smart cities need aggregate not individual data for infrastructure management while protecting privacy fundamentally.
Option c is incorrect because individual monitoring maximizes privacy invasion; utilities need system-level not personal consumption data for infrastructure planning and management purposes generally required operationally.
Option d is incorrect because public display would expose private consumption data; aggregation should protect not expose individual usage patterns for privacy protection absolutely necessary legally.

Correct Answer: Synchronized countdown

Synchronized countdown protocols coordinate start times accounting for network delays, ensuring fair simultaneous starts despite players' geographic distribution and varying connection latencies effectively managed throughout tournament operations precisely.
Option a is incorrect because local timing without coordination causes unfair advantages; tournaments need synchronized not independent starts for competitive fairness absolutely required fundamentally throughout competitions necessarily.
Option c is incorrect because random starts destroy competitive integrity; tournaments require simultaneous not staggered starts for fair competition among all participants equally treated fairly throughout.
Option d is incorrect because sequential joining creates time advantages for early starters; competitive gaming needs simultaneous not ordered starts for fairness fundamentally required absolutely essentially necessary.

Correct Answer: Adaptive learning

Adaptive learning continuously updates predictions based on recent sales patterns, adjusting to trends and seasonality better than static models ensuring inventory matches demand dynamically throughout operations effectively.
Option a is incorrect because static forecasting using fixed models becomes outdated as patterns change; retail needs adaptive not fixed predictions for accuracy over time continuously maintained.
Option c is incorrect because manual prediction can't process volumes of data or adapt quickly; modern retail needs automated learning not human guessing for scalability practically required.
Option d is incorrect because historical averaging misses trends and seasonality; sophisticated learning models capture patterns that simple averaging cannot detect for accurate forecasting needed essentially.

Correct Answer: Quality-of-service prioritization

Quality-of-service prioritization reserves bandwidth for medical consultations ensuring clear video and audio while limiting less critical transfers, maintaining healthcare service quality during remote consultations effectively throughout sessions continuously.
Option a is incorrect because equal bandwidth might degrade consultation quality when other applications compete; medical sessions need priority not equality for healthcare effectiveness fundamentally required absolutely necessary.
Option c is incorrect because random allocation could interrupt medical consultations; healthcare communications need guaranteed not chance-based bandwidth for reliability during critical consultations occurring regularly necessarily required.
Option d is incorrect because first-come bandwidth could prioritize background transfers over medical sessions; telemedicine needs intelligent not sequential bandwidth allocation for healthcare priority essentially required fundamentally.

Correct Answer: Terrain analysis

Terrain analysis uses computer vision to evaluate surface conditions, obstacles, and safety factors, dynamically selecting appropriate landing zones ensuring safe autonomous delivery operations effectively throughout missions performed continuously.
Option a is incorrect because random selection ignores safety hazards potentially causing crashes; drone delivery needs intelligent not arbitrary landing zone selection for operational safety fundamentally required.
Option c is incorrect because predetermined spots might become unavailable or unsafe; dynamic analysis adapts to current conditions unlike fixed locations potentially compromised over time occurring unpredictably.
Option d is incorrect because manual designation requires human involvement defeating autonomous operation purpose; drone delivery needs automatic not manual landing zone identification for scalability practically achievable.

Correct Answer: Digital rights management

Digital rights management controls access duration and copying, enabling libraries to lend digital content temporarily while protecting publisher rights through technological enforcement mechanisms implemented systematically throughout lending processes effectively.
Option a is incorrect because permanent downloads would deplete library resources; lending models need temporary not permanent access for sustainable digital collections maintained over time continuously.
Option c is incorrect because unlimited sharing violates copyright destroying the publishing economy; libraries need controlled not unrestricted distribution for legal compliance absolutely required fundamentally necessarily mandated.
Option d is incorrect because physical media doesn't address digital resource management; modern libraries need electronic not physical lending systems for digital content distribution effectively managed systematically.

Correct Answer: Multi-sensor integration

Multi-sensor integration correlates physiological, movement, and location data providing holistic performance analysis superior to individual metrics, enabling optimized training through comprehensive monitoring effectively throughout athletic sessions continuously performed.
Option a is incorrect because single metrics miss important performance relationships; comprehensive training analysis needs multiple not individual data streams for complete understanding fundamentally required essentially necessary.
Option c is incorrect because manual recording is error-prone and incomplete; athletic monitoring needs automatic comprehensive capture not selective human recording for accuracy absolutely required fundamentally.
Option d is incorrect because visual observation misses internal physiological data; modern training needs objective sensor data not subjective observation for scientific training optimization effectively achieved practically.

Correct Answer: Multi-factor authentication

Multi-factor authentication combines credentials like phones, codes, and biometrics, providing strong security while maintaining convenience through multiple verification options preventing unauthorized access effectively throughout usage continuously maintained systematically.
Option a is incorrect because single factors are easily compromised through theft or duplication; smart locks need multiple not single authentication factors for adequate security fundamentally required.
Option c is incorrect because no authentication defeats security purpose entirely; locks must verify identity not grant unrestricted access for basic security requirements absolutely necessary fundamentally.
Option d is incorrect because passwords alone are vulnerable to sharing and guessing; modern smart locks need stronger than password-only authentication for adequate protection effectively required essentially.