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Crypto
| Blockchain & Protocols
16-02-2026
Question 1 of 12
What is the primary purpose of a Merkle tree in blockchain technology?
To encrypt transaction data.
To speed up transaction processing.
To efficiently verify the integrity of a large dataset.
To secure consensus mechanisms.
Question 2 of 12
Which consensus mechanism is used by Bitcoin?
Proof-of-Work (PoW)
Proof-of-Authority (PoA)
Proof-of-Stake (PoS)
Delegated Proof-of-Stake (DPoS)
Question 3 of 12
What is the function of a
nonce
in the context of Bitcoin mining?
A random value used to find a hash below a target threshold.
It's the address of the next block.
The number of transactions in a block.
A timestamp of when the block was created.
Question 4 of 12
What is a smart contract?
A legal document stored on the blockchain.
A self-executing contract with the terms of the agreement directly written into code.
A physical contract that is notarized using blockchain technology.
A type of cryptocurrency.
Question 5 of 12
What does the term 'Byzantine Fault Tolerance' refer to in distributed systems like blockchains?
The amount of energy required to mine a block.
The speed at which transactions are processed.
The ability of a system to function even if some of its components fail or act maliciously.
The legal framework governing blockchain technology.
Question 6 of 12
What is the role of a 'gas limit' in the Ethereum blockchain?
It is the maximum amount of Ether that can be sent in a single transaction.
It sets the minimum price for Ether.
It is the maximum amount of gas a user is willing to spend on a transaction.
It limits the size of a smart contract that can be deployed.
Question 7 of 12
Which of the following is a common use case for Layer-2 scaling solutions in blockchain?
Reducing transaction fees and increasing transaction speeds.
Changing the consensus mechanism of the main blockchain.
Improving the security of the main blockchain.
Creating new cryptocurrencies.
Question 8 of 12
What is the main difference between a public and a private blockchain?
Public blockchains are more secure than private blockchains.
Public blockchains are faster than private blockchains.
Public blockchains are permissionless, while private blockchains are permissioned.
Public blockchains are only used for cryptocurrencies.
Question 9 of 12
What is a 51% attack?
An attack that targets cryptocurrency exchanges.
An attack where an attacker controls more than half of the network's computing power.
An attack that exploits vulnerabilities in smart contracts.
An attack that attempts to steal private keys.
Question 10 of 12
What is the purpose of a 'hard fork' in a blockchain?
To create a temporary copy of the blockchain for testing purposes.
To implement a change to the protocol that is not backward compatible.
To increase the block size.
To fix a bug in the blockchain software.
Please select an answer
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