Selected MCQ

Current Question
What is a block in blockchain composed of?
  • A. A list of IP addresses
  • B. A set of recent transactions and a reference to the previous block
  • C. A dictionary of passwords
  • D. A government-issued certificate
Correct Answer: B
Explanation:
A blockchain block contains a batch of transactions plus a hash linking to the previous block.
Related Question 1
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 2
What is a token in blockchain contexts?
  • A. A physical key
  • B. A digital asset representing value or rights
  • C. A password
  • D. VPN software
Correct Answer: B
Explanation:
In blockchain, a token is a digital unit of value or access rights recorded on the ledger.
Related Question 3
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 4
What is the main goal of blockchain's consensus mechanism?
  • A. To ensure every node has the same data
  • B. To shuffle tokens quickly
  • C. To encrypt all data
  • D. To generate a random number
Correct Answer: A
Explanation:
Consensus mechanisms such as PoW/PoS ensure that all nodes agree on a single history of transactions.
Related Question 5
What is a 'token' in blockchain context?
  • A. A physical key
  • B. A digital asset representing value or rights
  • C. A password
  • D. VPN software
Correct Answer: B
Explanation:
In blockchain, a token is a digital unit of value or access rights recorded on the ledger.