CCA Transactions & Verification 1 — Questions and Answers
Question 1: What does a blockchain transaction include?
- Username and password
- Digital signature and transaction details (Correct answer)
- Social Security number
- Email and phone number
Correct answer: Digital signature and transaction details
A blockchain transaction typically includes sender and receiver addresses, amount, timestamp, and a digital signature.
Question 2: How is a transaction verified on the blockchain?
- By scanning QR codes
- Using AI algorithms
- Through consensus among network nodes (Correct answer)
- By local storage
Correct answer: Through consensus among network nodes
Network nodes validate transactions using consensus mechanisms like Proof of Work or Proof of Stake.
Question 3: What is a hash in blockchain?
- Encrypted email
- A user password
- A cryptographic summary of data (Correct answer)
- Network firewall
Correct answer: A cryptographic summary of data
A hash is a unique digital fingerprint of data, used to verify integrity and link blocks securely.
Question 4: What prevents double-spending in blockchain?
- Bank approval
- Two-step authentication
- Consensus protocol validation (Correct answer)
- Manual auditing
Correct answer: Consensus protocol validation
Consensus mechanisms and public verification ensure a transaction is recorded only once on the blockchain.
Question 5: What is the role of a miner in transaction verification?
- They encrypt private keys
- They validate and add transactions to the ledger (Correct answer)
- They store user passwords
- They issue new cryptocurrencies
Correct answer: They validate and add transactions to the ledger
Miners solve complex problems to validate and add transactions to the blockchain, earning rewards for doing so.
Question 6: Why is immutability important in transaction verification?
- To enable refunds
- To increase storage capacity
- To ensure trust and prevent tampering (Correct answer)
- To allow user edits
Correct answer: To ensure trust and prevent tampering
Immutability ensures once a transaction is confirmed and recorded, it cannot be altered, supporting trust and auditability.
CCA Transactions & Verification 1
What does a blockchain transaction include?