CBSA Core Blockchain Principles 2

Question 1

What property of a Merkle tree allows efficient proof that a specific transaction is included in a block without downloading the entire blockchain?

Accepted Answer

Merkle proof (SPV proof)

Answer

Full node verification

Answer

Zero-knowledge proof

Answer

Ring signature

Question 2

In blockchain terminology, what does 'finality' refer to?

Accepted Answer

The guarantee that a confirmed transaction cannot be reversed

Answer

The last block ever added to the chain

Answer

The maximum block size limit

Answer

The process of burning tokens permanently

Question 3

Which type of blockchain fork occurs when nodes permanently diverge because they follow different protocol rules?

Accepted Answer

Hard fork

Answer

Soft fork

Answer

Orphan fork

Answer

Temporary fork

Question 4

What role does a cryptographic nonce serve in Proof of Work mining?

Accepted Answer

It is a number miners increment to find a hash meeting the difficulty target

Answer

It encrypts the transaction data

Answer

It identifies the miner's wallet address

Answer

It stores the block timestamp

Question 5

What is the primary purpose of the UTXO (Unspent Transaction Output) model used in Bitcoin?

Accepted Answer

To track coin ownership by recording spendable outputs rather than account balances

Answer

To compress block sizes

Answer

To enable smart contract execution

Answer

To anonymize sender addresses

Question 6

Which characteristic makes blockchain data immutable in practice?

Accepted Answer

Cryptographic chaining of blocks so altering one invalidates all subsequent blocks

Answer

Legal enforceability of the ledger

Answer

Centralized backups maintained by validators

Answer

Encryption of all stored data

Question 7

In a permissioned blockchain, what distinguishes it from a public blockchain regarding participation?

Accepted Answer

Participation requires identity verification and explicit authorization

Answer

Permissioned blockchains use no cryptography

Answer

Permissioned blockchains cannot execute smart contracts

Answer

All nodes must be in the same geographic region