Selected MCQ

Current Question
Which data structure uses the LIFO (Last In First Out) access method?
  • A. Queue
  • B. Stack
  • C. Graph
  • D. Hash table
Correct Answer: B
Explanation:
A stack uses Last-In-First-Out order for insertion and removal.
Related Question 1
Which cryptocurrency uses a blockchain but was the first to implement smart contracts?
  • A. Bitcoin
  • B. Ethereum
  • C. Litecoin
  • D. Ripple
Correct Answer: B
Explanation:
Ethereum introduced smart contracts on the blockchain.
Related Question 2
Which type of database is most suitable for handling unstructured or semi-structured data like JSON documents?
  • A. Relational (SQL)
  • B. NoSQL document store
  • C. Flat file
  • D. Spreadsheet
Correct Answer: B
Explanation:
NoSQL document databases (e.g., MongoDB) are designed to store and query unstructured data, such as JSON documents.
Related Question 3
What ensures blockchain data integrity across nodes?
  • A. Public database
  • B. Hash-linked blocks and consensus
  • C. Encryption keys only
  • D. Trusted server
Correct Answer: B
Explanation:
Blockchain uses cryptographic hashes linking blocks and consensus protocols to maintain integrity.
Related Question 4
Which concept involves using sensor data to create a 3D model of a city or facility?
  • A. Digital wallet
  • B. Digital twin
  • C. Virtual machine
  • D. Quantum replica
Correct Answer: B
Explanation:
Digital twins can model entire environments or systems in real-time using sensor data.
Related Question 5
What is a common method for brute-forcing network passwords?
  • A. SQL injection
  • B. Dictionary attack
  • C. DNS spoofing
  • D. Packet sniffing
Correct Answer: B
Explanation:
A dictionary attack tries many possible passwords from a wordlist to guess credentials.