1.
Who created Bitcoin?
Correct Answer
A. Satoshi Nakamoto
Explanation
Satoshi Nakamoto is credited with creating Bitcoin. Although the true identity of Satoshi Nakamoto remains unknown, this pseudonymous individual or group published the Bitcoin whitepaper in 2008 and developed the first implementation of the cryptocurrency in 2009. Satoshi Nakamoto's creation of Bitcoin revolutionized the financial industry by introducing a decentralized digital currency system that operates without the need for intermediaries such as banks.
2.
What is a miner?
Correct Answer
C. A person doing calculations to verify a transaction
Explanation
A miner is a person who performs calculations to verify a transaction on the blockchain. They use their computational power to solve complex mathematical problems, which helps in confirming the validity of transactions and adding them to the blockchain. Miners play a crucial role in maintaining the integrity and security of the blockchain network.
3.
Where can you buy a cryptocurrency?
Correct Answer
D. All of the above
Explanation
Cryptocurrencies can be bought through a private transaction, where individuals can directly buy from others. They can also be bought through an exchange, which is a platform that facilitates the buying and selling of cryptocurrencies. Additionally, cryptocurrencies can be purchased from a Bitcoin ATM, which allows users to exchange cash for cryptocurrencies. Therefore, all of the options mentioned (private transaction, exchange, and Bitcoin ATM) are valid ways to buy a cryptocurrency.
4.
What is a blockchain?
Correct Answer
A. A distributed ledger on a peer to peer network
Explanation
A blockchain is a distributed ledger on a peer-to-peer network. This means that instead of being stored in a central location, the ledger is replicated and stored on multiple computers or nodes within the network. Each node has a copy of the entire blockchain and participates in verifying and validating transactions. This decentralized nature of a blockchain ensures transparency, security, and immutability of the data recorded on it.
5.
What is the purpose of a nonce?
Correct Answer
C. Prevents double spending
Explanation
A nonce is used to prevent double spending. In the context of cryptocurrencies, double spending refers to the act of spending the same digital currency more than once. By including a nonce in a transaction, it adds a random number or value that changes with each transaction, making it unique. This uniqueness ensures that the transaction cannot be duplicated or tampered with, thus preventing double spending.
6.
What incentivizes the miners to give correct validation of transactions?
Correct Answer
B. A block reward
Explanation
Miners are incentivized to give correct validation of transactions through a block reward. This reward is typically in the form of cryptocurrency, such as Bitcoin, and is given to the miner who successfully solves the mathematical problem required to add a new block to the blockchain. By providing this reward, miners are motivated to expend computational resources and compete with each other to validate transactions accurately, ensuring the security and integrity of the blockchain network.
7.
What powers the Ethereum Virtual Machine?
Correct Answer
A. Gas
Explanation
Gas powers the Ethereum Virtual Machine. Gas is a unit of measurement used to quantify the amount of computational effort required to execute operations or run programs on the Ethereum network. It is used to allocate resources and determine the cost of executing smart contracts and transactions. Gas fees are paid in Ether, the native cryptocurrency of the Ethereum network, and are used to incentivize miners to include transactions in blocks and secure the network. Therefore, gas is the correct answer as it is the fuel that powers the Ethereum Virtual Machine.
8.
What is Proof of Stake?
Correct Answer
D. A transaction and block verification protocol
Explanation
Proof of Stake is a transaction and block verification protocol used in blockchain technology. It is an alternative to Proof of Work, where participants in a network validate transactions and create new blocks based on the number of coins they hold. In Proof of Stake, the probability of creating a new block is determined by the number of coins a participant has, rather than computational power. This protocol ensures the security and integrity of the blockchain network by preventing malicious activities and double-spending.
9.
Bitcoin is based on ______ Blockchain.
Correct Answer
A. PublicĀ
Explanation
Bitcoin is based on a public Blockchain. This means that the transactions and data recorded on the Bitcoin Blockchain are accessible to anyone who wants to view or verify them. The public nature of the Blockchain allows for transparency and trust in the Bitcoin network, as anyone can participate in the validation process and ensure the integrity of the transactions. Additionally, the public Blockchain ensures that no single entity or authority has control over the Bitcoin network, making it decentralized and resistant to censorship or manipulation.
10.
Each block of blockchain consists of which of the following?
Correct Answer
D. All of the above
Explanation
Each block of a blockchain consists of a hash pointer to the previous block, a timestamp, and a list of transactions. The hash pointer ensures the integrity and continuity of the blockchain by linking each block to its previous block. The timestamp records the time at which the block is added to the blockchain, providing a chronological order. The list of transactions contains the data or information that is being recorded on the blockchain. Therefore, all of the given options are correct and are essential components of a block in a blockchain.
11.
Hash identifying each block in the Blockchain is generated using which of the following cryptographic algorithm.
Correct Answer
B. SHA256
Explanation
The correct answer is SHA256. SHA256 is a cryptographic algorithm used to generate a unique hash for each block in the Blockchain. This algorithm takes an input and produces a fixed-size 256-bit hash value, which is unique to the input data. This hash value ensures the integrity and security of the Blockchain network by providing a unique identifier for each block.
12.
In Blockchain, blocks are linked.
Correct Answer
A. Backward to the previous block
Explanation
In Blockchain, blocks are linked backward to the previous block. This means that each block contains a reference to the previous block's hash, creating a chain of blocks. This linking ensures the integrity and security of the blockchain as any modification to a block will change its hash, making it invalid and breaking the chain. By linking blocks in this way, the entire history of transactions in the blockchain can be traced back to the very first block, providing transparency and immutability to the system.
13.
The primary benefit of immutability is:
Correct Answer
C. Tamper ProofIncreased Efficiency
Explanation
The primary benefit of immutability is that it ensures tamper-proof data and increased efficiency. When data is immutable, it cannot be modified or tampered with, providing a higher level of security. Additionally, immutable data allows for more efficient operations and optimizations since it eliminates the need for constant checks and updates. Therefore, immutability offers the benefits of tamper-proofing data and improving overall efficiency.
14.
What are different types of tokens?
Correct Answer
D. All of the above
Explanation
The correct answer is "All of the above" because tokens can refer to different things depending on the context. In the given question, the types of tokens mentioned are platform tokens, privacy tokens, and currency tokens. Therefore, all of these options are correct types of tokens.
15.
Blockchain can be stored in which of the following?
Correct Answer
C. Both of the above
Explanation
Blockchain can be stored in both a flat file and a database. A flat file is a simple text file that stores data in a plain, unstructured format, while a database is a structured collection of data that allows for efficient storage, retrieval, and manipulation. Blockchain technology can be implemented using either of these storage methods, depending on the specific requirements and design of the blockchain system.