1
What is a blockchain?
- A
A decentralized, distributed digital ledger
- B
A type of cryptocurrency
- C
A centralized database
- D
A programming language
Show AnswerHide Answer
✓ A. A decentralized, distributed digital ledger
🎯 120+ Questions • Updated 2026
Blockchain
Multiple Choice Questions
Master Blockchain concepts with 120+ curated MCQs covering Bitcoin, Ethereum, smart contracts, consensus mechanisms, DeFi, NFTs, and more. Perfect for exams, interviews, and placement preparation.
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📝Blockchain MCQs(120 questions)
2
What is the primary purpose of blockchain technology?
- A
To enable secure, transparent, and tamper-proof transactions
- B
To replace all traditional banks
- C
To create a global currency
- D
To mine cryptocurrency
Show AnswerHide Answer
✓ A. To enable secure, transparent, and tamper-proof transactions
3
What is a block in a blockchain?
- A
A collection of transactions bundled together
- B
A single transaction
- C
The entire chain of records
- D
A cryptographic key
Show AnswerHide Answer
✓ A. A collection of transactions bundled together
4
What links blocks together in a blockchain?
- A
The previous block's hash
- B
The block's timestamp
- C
The block's transactions
- D
The block's size
Show AnswerHide Answer
✓ A. The previous block's hash
5
What is a hash function in blockchain?
- A
A mathematical function that converts input into a fixed-length string
- B
A type of cryptocurrency
- C
A consensus algorithm
- D
A digital signature
Show AnswerHide Answer
✓ A. A mathematical function that converts input into a fixed-length string
6
What is the difference between public and private blockchain?
- A
Public is open to anyone, private is restricted to authorized participants
- B
Public is faster than private
- C
Private is more secure than public
- D
Public uses proof-of-work, private uses proof-of-stake
Show AnswerHide Answer
✓ A. Public is open to anyone, private is restricted to authorized participants
7
Who is the founder of Bitcoin?
- A
Satoshi Nakamoto
- B
Vitalik Buterin
- C
Charles Hoskinson
- D
Gavin Wood
Show AnswerHide Answer
✓ A. Satoshi Nakamoto
8
On which blockchain is Bitcoin based?
- A
Public blockchain
- B
Private blockchain
- C
Permissioned blockchain
- D
Hybrid blockchain
Show AnswerHide Answer
✓ A. Public blockchain
9
What is the consensus mechanism used by Bitcoin?
- A
Proof of Work (PoW)
- B
Proof of Stake (PoS)
- C
Delegated Proof of Stake (DPoS)
- D
Proof of Authority (PoA)
Show AnswerHide Answer
✓ A. Proof of Work (PoW)
10
What is the maximum supply of Bitcoin?
- A
21 million
- B
100 million
- C
1 billion
- D
Unlimited
Show AnswerHide Answer
✓ A. 21 million
11
What is a Bitcoin halving?
- A
The reward for mining Bitcoin is reduced by half
- B
The block time is halved
- C
The price is halved
- D
The number of transactions is halved
Show AnswerHide Answer
✓ A. The reward for mining Bitcoin is reduced by half
12
What is the smallest unit of Bitcoin?
- A
Satoshi
- B
Wei
- C
Gwei
- D
Ether
Show AnswerHide Answer
✓ A. Satoshi
13
Who is the founder of Ethereum?
- A
Vitalik Buterin
- B
Satoshi Nakamoto
- C
Charles Hoskinson
- D
Gavin Wood
Show AnswerHide Answer
✓ A. Vitalik Buterin
14
What is the native cryptocurrency of Ethereum?
- A
Ether (ETH)
- B
Bitcoin (BTC)
- C
Litecoin (LTC)
- D
Cardano (ADA)
Show AnswerHide Answer
✓ A. Ether (ETH)
15
What is a smart contract?
- A
A self-executing contract with the terms directly written into code
- B
A legal document on the blockchain
- C
A type of token
- D
A consensus algorithm
Show AnswerHide Answer
✓ A. A self-executing contract with the terms directly written into code
16
What is the Ethereum Virtual Machine (EVM)?
- A
A runtime environment for executing smart contracts
- B
A type of cryptocurrency
- C
A consensus mechanism
- D
A mining pool
Show AnswerHide Answer
✓ A. A runtime environment for executing smart contracts
17
What is the token standard for fungible tokens on Ethereum?
- A
ERC-20
- B
ERC-721
- C
ERC-1155
- D
ERC-777
Show AnswerHide Answer
✓ A. ERC-20
18
What is the token standard for non-fungible tokens (NFTs) on Ethereum?
- A
ERC-721
- B
ERC-20
- C
ERC-1155
- D
ERC-777
Show AnswerHide Answer
✓ A. ERC-721
19
What is Proof of Work (PoW)?
- A
A consensus mechanism requiring miners to solve complex puzzles
- B
A mechanism where validators stake coins to validate blocks
- C
A mechanism where users vote on block validity
- D
A mechanism that uses authorities to validate
Show AnswerHide Answer
✓ A. A consensus mechanism requiring miners to solve complex puzzles
20
What is Proof of Stake (PoS)?
- A
A consensus mechanism where validators stake their coins to propose and validate blocks
- B
A mechanism that uses mining
- C
A mechanism that uses authorities
- D
A mechanism that uses voting
Show AnswerHide Answer
✓ A. A consensus mechanism where validators stake their coins to propose and validate blocks
21
Which blockchain uses Delegated Proof of Stake (DPoS)?
- A
EOS
- B
Bitcoin
- C
Ethereum
- D
Monero
Show AnswerHide Answer
✓ A. EOS
22
What is a 51% attack?
- A
An attack where a single entity controls more than 50% of the network's mining power
- B
An attack where 51% of the nodes are offline
- C
An attack where 51% of transactions are reverted
- D
An attack where 51% of users lose their wallets
Show AnswerHide Answer
✓ A. An attack where a single entity controls more than 50% of the network's mining power
23
What is the purpose of a consensus mechanism in blockchain?
- A
To achieve agreement on the state of the ledger among distributed nodes
- B
To mine new coins
- C
To create smart contracts
- D
To encrypt transactions
Show AnswerHide Answer
✓ A. To achieve agreement on the state of the ledger among distributed nodes
24
Which consensus mechanism does Ethereum 2.0 use?
- A
Proof of Stake (PoS)
- B
Proof of Work (PoW)
- C
Delegated Proof of Stake (DPoS)
- D
Proof of Authority (PoA)
Show AnswerHide Answer
✓ A. Proof of Stake (PoS)
25
What is a smart contract?
- A
A self-executing contract with the terms of the agreement directly written into code
- B
A paper contract that is digitized
- C
A legal document that is not enforceable
- D
A type of digital signature
Show AnswerHide Answer
✓ A. A self-executing contract with the terms of the agreement directly written into code
26
Which programming language is commonly used for writing smart contracts on Ethereum?
- A
Solidity
- B
JavaScript
- C
Python
- D
C++
Show AnswerHide Answer
✓ A. Solidity
27
What is a decentralized application (dApp) built on smart contracts?
- A
An application that runs on a blockchain
- B
An application that runs on a single server
- C
An application that uses centralized databases
- D
An application that cannot be used without authorization
Show AnswerHide Answer
✓ A. An application that runs on a blockchain
28
What is the gas fee in Ethereum?
- A
A fee paid to execute transactions and smart contracts
- B
A tax on cryptocurrency gains
- C
A fee to create a new account
- D
A fee to transfer tokens
Show AnswerHide Answer
✓ A. A fee paid to execute transactions and smart contracts
29
What is the main advantage of using smart contracts?
- A
They are automatically executed without intermediaries
- B
They are cheaper than traditional contracts
- C
They are more secure
- D
They are faster to write
Show AnswerHide Answer
✓ A. They are automatically executed without intermediaries
30
Can smart contracts be updated after deployment?
- A
No, they are immutable once deployed
- B
Yes, they can be updated by the owner
- C
Yes, but only through a governance vote
- D
Yes, they can be deleted and redeployed
Show AnswerHide Answer
✓ A. No, they are immutable once deployed (though upgradeable patterns exist)
31
What is cryptocurrency?
- A
Digital or virtual currency that uses cryptography for security
- B
Physical money that is stored in banks
- C
A type of stock
- D
A government-issued currency
Show AnswerHide Answer
✓ A. Digital or virtual currency that uses cryptography for security
32
Which of the following is a type of cryptocurrency?
- A
Bitcoin
- B
Ethereum
- C
Litecoin
- D
All of the above
Show AnswerHide Answer
✓ D. All of the above
33
What is a token in cryptocurrency?
- A
A digital asset created on top of an existing blockchain
- B
The same as a coin
- C
A physical token used for payment
- D
A type of mining reward
Show AnswerHide Answer
✓ A. A digital asset created on top of an existing blockchain
34
What are the different types of tokens in cryptocurrency?
- A
Currency, privacy, and platform tokens
- B
Only currency tokens
- C
Only privacy tokens
- D
Only platform tokens
Show AnswerHide Answer
✓ A. Currency, privacy, and platform tokens
35
What is a stablecoin?
- A
A cryptocurrency pegged to a stable asset like USD
- B
A cryptocurrency that does not change in value
- C
A type of mining hardware
- D
A coin that is not traded
Show AnswerHide Answer
✓ A. A cryptocurrency pegged to a stable asset like USD
36
What is the market capitalization of a cryptocurrency?
- A
The total value of all coins in circulation multiplied by the price
- B
The total number of coins ever created
- C
The price of a single coin
- D
The trading volume
Show AnswerHide Answer
✓ A. The total value of all coins in circulation multiplied by the price
37
What is a cryptocurrency wallet?
- A
A software or hardware that stores private and public keys
- B
A physical wallet for holding cash
- C
A bank account for cryptocurrency
- D
A type of exchange
Show AnswerHide Answer
✓ A. A software or hardware that stores private and public keys
38
Where is cryptocurrency stored?
- A
In a wallet
- B
In a bank account
- C
On a credit card
- D
On a USB drive
Show AnswerHide Answer
✓ A. In a wallet
39
What is the difference between a hot wallet and a cold wallet?
- A
Hot wallet is connected to the internet, cold wallet is offline
- B
Hot wallet is for large amounts, cold wallet for small
- C
Hot wallet is free, cold wallet is paid
- D
Hot wallet is used for trading, cold wallet for saving
Show AnswerHide Answer
✓ A. Hot wallet is connected to the internet, cold wallet is offline
40
What is a private key in a wallet?
- A
A secret code that allows you to access and manage your cryptocurrency
- B
A public address to receive funds
- C
A password for the exchange
- D
A key for mining
Show AnswerHide Answer
✓ A. A secret code that allows you to access and manage your cryptocurrency
41
What is a seed phrase in a wallet?
- A
A list of words that can recover a wallet
- B
A phrase used to encrypt transactions
- C
A phrase for mining
- D
A phrase for trading
Show AnswerHide Answer
✓ A. A list of words that can recover a wallet
42
What is a multi-signature wallet?
- A
A wallet that requires multiple private keys to authorize a transaction
- B
A wallet with multiple currencies
- C
A wallet that can be accessed from multiple devices
- D
A wallet with multiple users
Show AnswerHide Answer
✓ A. A wallet that requires multiple private keys to authorize a transaction
43
What is mining in blockchain?
- A
The process of validating transactions and adding them to the blockchain
- B
Extracting physical minerals
- C
Creating new cryptocurrencies
- D
Storing data on the blockchain
Show AnswerHide Answer
✓ A. The process of validating transactions and adding them to the blockchain
44
What is a miner in terms of blockchain?
- A
Computers that validate and process blockchain transactions
- B
A person who mines gold
- C
Transaction picking algorithm
- D
Calculation of hash
Show AnswerHide Answer
✓ A. Computers that validate and process blockchain transactions
45
What is a mining pool?
- A
A group of miners who combine their computational power to increase chances of finding a block
- B
A single miner
- C
A pool of cryptocurrencies
- D
A type of wallet
Show AnswerHide Answer
✓ A. A group of miners who combine their computational power to increase chances of finding a block
46
What is the block reward in Bitcoin?
- A
The number of bitcoins given to a miner for successfully mining a block
- B
The fee paid by users for transactions
- C
The total supply of bitcoins
- D
The hash rate
Show AnswerHide Answer
✓ A. The number of bitcoins given to a miner for successfully mining a block
47
What is hashing in mining?
- A
The process of converting input data into a fixed-size string of characters
- B
The process of guessing the private key
- C
The process of creating a new block
- D
The process of signing transactions
Show AnswerHide Answer
✓ A. The process of converting input data into a fixed-size string of characters
48
What is the difficulty in mining?
- A
A measure of how hard it is to find a new block
- B
The number of miners on the network
- C
The price of the cryptocurrency
- D
The number of transactions
Show AnswerHide Answer
✓ A. A measure of how hard it is to find a new block
49
What is a fork in blockchain?
- A
A split in the blockchain due to protocol changes
- B
A type of transaction
- C
A new cryptocurrency
- D
A mining pool
Show AnswerHide Answer
✓ A. A split in the blockchain due to protocol changes
50
What is a hard fork?
- A
A fork that is not backward-compatible
- B
A fork that is backward-compatible
- C
A fork that creates a new coin
- D
A fork that does not split the chain
Show AnswerHide Answer
✓ A. A fork that is not backward-compatible
51
What is a soft fork?
- A
A fork that is backward-compatible
- B
A fork that creates a new blockchain
- C
A fork that requires new mining hardware
- D
A fork that is not backward-compatible
Show AnswerHide Answer
✓ A. A fork that is backward-compatible
52
What is the term for when a blockchain splits?
- A
Fork
- B
Split
- C
Divide
- D
None of the above
Show AnswerHide Answer
✓ A. Fork
53
Which fork resulted in the creation of Bitcoin Cash?
- A
Hard fork from Bitcoin
- B
Soft fork from Bitcoin
- C
Hard fork from Ethereum
- D
Soft fork from Ethereum
Show AnswerHide Answer
✓ A. Hard fork from Bitcoin
54
What is a governance fork?
- A
A fork that occurs due to disagreements in community governance
- B
A fork that changes the mining algorithm
- C
A fork that splits the blockchain in two
- D
A fork that is not consensus-based
Show AnswerHide Answer
✓ A. A fork that occurs due to disagreements in community governance
55
What is the impact of information leaks on an organization?
- A
Loss of reputation
- B
Loss of revenue
- C
Loss of customer trust
- D
All of the above
Show AnswerHide Answer
✓ D. All of the above
56
What is a 51% attack?
- A
A situation where a miner or group controls more than half of the network's mining power
- B
A type of hacking attack
- C
A phishing attack
- D
A virus on the blockchain
Show AnswerHide Answer
✓ A. A situation where a miner or group controls more than half of the network's mining power
57
What is the role of cryptography in blockchain security?
- A
To secure transactions and control the creation of new coins
- B
To provide user anonymity
- C
To encrypt the entire blockchain
- D
To secure the network from DDoS attacks
Show AnswerHide Answer
✓ A. To secure transactions and control the creation of new coins
58
What is a private key?
- A
A secret key used to sign transactions and prove ownership
- B
A public key used to receive funds
- C
A password for the wallet
- D
A key for mining
Show AnswerHide Answer
✓ A. A secret key used to sign transactions and prove ownership
59
What is a public key?
- A
A key used to receive cryptocurrency
- B
A key used to sign transactions
- C
A key used to encrypt data
- D
A key used to mine
Show AnswerHide Answer
✓ A. A key used to receive cryptocurrency
60
What is a double-spending attack?
- A
An attack where the same cryptocurrency is spent more than once
- B
An attack where the network is doubled
- C
An attack where miners double their rewards
- D
An attack where users double their coins
Show AnswerHide Answer
✓ A. An attack where the same cryptocurrency is spent more than once
61
What does decentralization mean in blockchain?
- A
No single entity controls the network
- B
The network is controlled by a central authority
- C
The network is controlled by a few large entities
- D
The network is controlled by the government
Show AnswerHide Answer
✓ A. No single entity controls the network
62
What is a decentralized application (dApp)?
- A
An application that runs on a decentralized network
- B
An application that runs on a centralized server
- C
An application that is controlled by a single authority
- D
An application that does not require a user interface
Show AnswerHide Answer
✓ A. An application that runs on a decentralized network
63
What is a Decentralized Autonomous Organization (DAO)?
- A
An organization governed by smart contracts without a central authority
- B
A traditional organization with a CEO
- C
A government agency
- D
A type of cryptocurrency
Show AnswerHide Answer
✓ A. An organization governed by smart contracts without a central authority
64
What is a node in a blockchain network?
- A
A computer that maintains a copy of the blockchain and participates in the network
- B
A transaction
- C
A block
- D
A wallet
Show AnswerHide Answer
✓ A. A computer that maintains a copy of the blockchain and participates in the network
65
What is the benefit of decentralization?
- A
Increased security and resistance to censorship
- B
Faster transactions
- C
Lower energy consumption
- D
Higher profitability
Show AnswerHide Answer
✓ A. Increased security and resistance to censorship
66
What is the role of miners in a decentralized network?
- A
They validate and secure transactions
- B
They create new coins
- C
They govern the network
- D
They design smart contracts
Show AnswerHide Answer
✓ A. They validate and secure transactions
67
What is a typical use case of blockchain beyond cryptocurrency?
- A
Supply chain management
- B
Voting systems
- C
Healthcare records
- D
All of the above
Show AnswerHide Answer
✓ D. All of the above
68
How can blockchain be used in supply chain?
- A
To track the provenance and movement of goods
- B
To pay for goods
- C
To create invoices
- D
To store product images
Show AnswerHide Answer
✓ A. To track the provenance and movement of goods
69
What is a smart contract used for in real estate?
- A
To automate property transfers and escrow
- B
To pay property taxes
- C
To store property deeds
- D
To manage maintenance requests
Show AnswerHide Answer
✓ A. To automate property transfers and escrow
70
How can blockchain improve voting systems?
- A
By providing a transparent and tamper-proof record of votes
- B
By allowing remote voting without security
- C
By eliminating the need for voters
- D
By counting votes faster
Show AnswerHide Answer
✓ A. By providing a transparent and tamper-proof record of votes
71
What is a digital identity on blockchain?
- A
A decentralized identity that users control
- B
A government-issued ID
- C
A social media profile
- D
A username on an exchange
Show AnswerHide Answer
✓ A. A decentralized identity that users control
72
What is the role of blockchain in healthcare?
- A
To securely store patient records and share them with authorized parties
- B
To replace doctors
- C
To mine patient data
- D
To issue medical bills
Show AnswerHide Answer
✓ A. To securely store patient records and share them with authorized parties
73
What is the scalability problem in blockchain?
- A
The inability to process a large number of transactions quickly
- B
The inability to store large amounts of data
- C
The inability to add new nodes
- D
The inability to create new blocks
Show AnswerHide Answer
✓ A. The inability to process a large number of transactions quickly
74
What is a Layer 2 solution in blockchain?
- A
A protocol built on top of the main blockchain to improve scalability
- B
A new blockchain
- C
A sidechain
- D
A hard fork
Show AnswerHide Answer
✓ A. A protocol built on top of the main blockchain to improve scalability
75
What is the Lightning Network?
- A
A Layer 2 scaling solution for Bitcoin
- B
A new cryptocurrency
- C
A mining pool
- D
A wallet
Show AnswerHide Answer
✓ A. A Layer 2 scaling solution for Bitcoin
76
What is sharding in blockchain?
- A
A technique to split the blockchain into smaller parts to increase throughput
- B
A way to mine multiple blocks at once
- C
A consensus mechanism
- D
A type of fork
Show AnswerHide Answer
✓ A. A technique to split the blockchain into smaller parts to increase throughput
77
What is the transaction throughput of Bitcoin?
- A
Approximately 7 transactions per second
- B
Approximately 100 transactions per second
- C
Approximately 1,000 transactions per second
- D
Approximately 10,000 transactions per second
Show AnswerHide Answer
✓ A. Approximately 7 transactions per second
78
What is the block size limit in Bitcoin?
- A
1 MB
- B
2 MB
- C
4 MB
- D
8 MB
Show AnswerHide Answer
✓ A. 1 MB
79
What is interoperability in blockchain?
- A
The ability of different blockchain networks to communicate and share data
- B
The ability of a blockchain to process more transactions
- C
The ability of a blockchain to store more data
- D
The ability of a blockchain to be upgraded
Show AnswerHide Answer
✓ A. The ability of different blockchain networks to communicate and share data
80
What is a blockchain bridge?
- A
A connection that allows assets and data to move between blockchains
- B
A physical bridge
- C
A type of wallet
- D
A consensus mechanism
Show AnswerHide Answer
✓ A. A connection that allows assets and data to move between blockchains
81
What is a sidechain?
- A
A separate blockchain that is connected to a main blockchain
- B
A type of transaction
- C
A mining algorithm
- D
A smart contract
Show AnswerHide Answer
✓ A. A separate blockchain that is connected to a main blockchain
82
What is the purpose of cross-chain communication?
- A
To enable interoperability and transfer of value between blockchains
- B
To increase block size
- C
To improve mining efficiency
- D
To centralize the network
Show AnswerHide Answer
✓ A. To enable interoperability and transfer of value between blockchains
83
What is Polkadot known for?
- A
Interoperability between multiple blockchains
- B
High scalability
- C
Privacy
- D
Smart contracts
Show AnswerHide Answer
✓ A. Interoperability between multiple blockchains
84
What is a wrapped token?
- A
A token that represents another asset on a different blockchain
- B
A token that is wrapped in a smart contract
- C
A token that is hidden
- D
A token that is encrypted
Show AnswerHide Answer
✓ A. A token that represents another asset on a different blockchain
85
What is a privacy coin?
- A
A cryptocurrency that focuses on hiding transaction details
- B
A coin that is not regulated
- C
A coin with high liquidity
- D
A coin that is used for privacy policies
Show AnswerHide Answer
✓ A. A cryptocurrency that focuses on hiding transaction details
86
Which of the following is a privacy coin?
- A
Monero
- B
Zcash
- C
Dash
- D
All of the above
Show AnswerHide Answer
✓ D. All of the above
87
What is a zk-SNARK?
- A
A cryptographic proof that allows transactions to be verified without revealing the details
- B
A type of mining algorithm
- C
A consensus mechanism
- D
A wallet type
Show AnswerHide Answer
✓ A. A cryptographic proof that allows transactions to be verified without revealing the details
88
What is the purpose of ring signatures?
- A
To hide the sender of a transaction among a group
- B
To encrypt the transaction data
- C
To sign the transaction with multiple keys
- D
To increase transaction speed
Show AnswerHide Answer
✓ A. To hide the sender of a transaction among a group
89
What is a stealth address?
- A
A one-time address used to receive funds to protect privacy
- B
A permanent address
- C
A public address
- D
A mining address
Show AnswerHide Answer
✓ A. A one-time address used to receive funds to protect privacy
90
What is the trade-off of privacy coins?
- A
They may be used for illicit activities
- B
They have lower scalability
- C
They are less secure
- D
They are more centralized
Show AnswerHide Answer
✓ A. They may be used for illicit activities
91
What is on-chain governance?
- A
A governance mechanism where decisions are made through blockchain-based voting
- B
A governance mechanism off the blockchain
- C
A type of consensus
- D
A type of fork
Show AnswerHide Answer
✓ A. A governance mechanism where decisions are made through blockchain-based voting
92
What is off-chain governance?
- A
Governance decisions made outside the blockchain
- B
Governance decisions made through smart contracts
- C
Governance decisions made by miners
- D
Governance decisions made by the community
Show AnswerHide Answer
✓ A. Governance decisions made outside the blockchain
93
What is a DAO?
- A
A Decentralized Autonomous Organization
- B
A Distributed Application Organization
- C
A Digital Asset Operation
- D
A Direct Access Order
Show AnswerHide Answer
✓ A. A Decentralized Autonomous Organization
94
What is a governance token?
- A
A token that allows holders to vote on protocol decisions
- B
A token that is used for mining
- C
A token that is used for staking
- D
A token that is used for transactions
Show AnswerHide Answer
✓ A. A token that allows holders to vote on protocol decisions
95
What is the role of a governance proposal?
- A
To suggest changes to the protocol
- B
To mine new blocks
- C
To create new tokens
- D
To validate transactions
Show AnswerHide Answer
✓ A. To suggest changes to the protocol
96
What is a constitutional blockchain?
- A
A blockchain with a formal constitution that governs its operation
- B
A blockchain used by governments
- C
A blockchain that cannot be forked
- D
A blockchain that is regulated
Show AnswerHide Answer
✓ A. A blockchain with a formal constitution that governs its operation
97
What does NFT stand for?
- A
Non-Fungible Token
- B
Non-Fungible Transaction
- C
Network Fungible Token
- D
New Finance Token
Show AnswerHide Answer
✓ A. Non-Fungible Token
98
What does 'non-fungible' mean?
- A
Unique and not interchangeable
- B
Interchangeable
- C
Fungible
- D
Divisible
Show AnswerHide Answer
✓ A. Unique and not interchangeable
99
What is the most common token standard for NFTs on Ethereum?
- A
ERC-721
- B
ERC-20
- C
ERC-1155
- D
ERC-777
Show AnswerHide Answer
✓ A. ERC-721
100
What is an NFT primarily used for?
- A
Representing ownership of digital assets like art, music, collectibles
- B
Sending payments
- C
Mining
- D
Staking
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✓ A. Representing ownership of digital assets like art, music, collectibles
101
Where are NFTs stored?
- A
On the blockchain
- B
On a centralized server
- C
On a wallet
- D
On a hard drive
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✓ A. On the blockchain
102
What is the difference between an NFT and a cryptocurrency?
- A
NFTs are unique, cryptocurrencies are fungible
- B
Cryptocurrencies are unique, NFTs are fungible
- C
Both are the same
- D
NFTs cannot be traded
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✓ A. NFTs are unique, cryptocurrencies are fungible
103
What does DeFi stand for?
- A
Decentralized Finance
- B
Distributed Finance
- C
Digital Finance
- D
Direct Finance
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✓ A. Decentralized Finance
104
What is the purpose of DeFi?
- A
To create an open, permissionless financial system
- B
To replace traditional banks
- C
To centralize finance
- D
To increase government control
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✓ A. To create an open, permissionless financial system
105
What is a DEX in DeFi?
- A
Decentralized Exchange
- B
Digital Exchange
- C
Direct Exchange
- D
Distributed Exchange
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✓ A. Decentralized Exchange
106
What is yield farming?
- A
The process of staking or lending crypto to earn rewards
- B
Mining for new coins
- C
Buying and selling tokens
- D
Creating NFTs
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✓ A. The process of staking or lending crypto to earn rewards
107
What is liquidity provision in DeFi?
- A
Supplying assets to a decentralized exchange to enable trading
- B
Mining blocks
- C
Creating new tokens
- D
Governance voting
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✓ A. Supplying assets to a decentralized exchange to enable trading
108
What is an automated market maker (AMM)?
- A
A smart contract that automatically creates liquidity pools and determines prices
- B
A person who makes markets
- C
A centralized exchange
- D
A mining pool
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✓ A. A smart contract that automatically creates liquidity pools and determines prices
109
What is a security token?
- A
A token that represents ownership in a real-world asset, subject to regulations
- B
A token used for security purposes
- C
A token that is not tradable
- D
A token for mining
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✓ A. A token that represents ownership in a real-world asset, subject to regulations
110
What is an STO?
- A
Security Token Offering
- B
Simple Token Offering
- C
Standard Token Offering
- D
Smart Token Offering
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✓ A. Security Token Offering
111
How are security tokens different from utility tokens?
- A
Security tokens represent investment contracts; utility tokens provide access to a service
- B
Security tokens are used for governance; utility tokens for transactions
- C
They are the same
- D
Security tokens are for games; utility tokens for finance
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✓ A. Security tokens represent investment contracts; utility tokens provide access to a service
112
What is the regulatory status of security tokens?
- A
They are often subject to securities laws
- B
They are unregulated
- C
They are banned
- D
They are only allowed in some countries
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✓ A. They are often subject to securities laws
113
What is the purpose of a security token?
- A
To represent ownership in a company or asset
- B
To pay for services
- C
To mine blocks
- D
To govern a protocol
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✓ A. To represent ownership in a company or asset
114
What is a blockchain-based security?
- A
A security token issued on a blockchain
- B
A traditional security
- C
A mining contract
- D
A smart contract security
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✓ A. A security token issued on a blockchain
115
What is a blockchain oracle?
- A
A service that provides external data to smart contracts
- B
A type of node
- C
A mining algorithm
- D
A wallet
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✓ A. A service that provides external data to smart contracts
116
Why are oracles needed in blockchain?
- A
Blockchains cannot access off-chain data directly
- B
To increase transaction speed
- C
To reduce fees
- D
To mine more efficiently
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✓ A. Blockchains cannot access off-chain data directly
117
What is a decentralized oracle network?
- A
A network of multiple oracles to ensure data reliability
- B
A single oracle
- C
A centralized oracle
- D
A type of smart contract
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✓ A. A network of multiple oracles to ensure data reliability
118
Which project is known for providing decentralized oracles?
- A
Chainlink
- B
Polkadot
- C
Solana
- D
Cardano
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✓ A. Chainlink
119
What type of data can an oracle provide?
- A
Price feeds, weather data, sports scores, etc.
- B
Only financial data
- C
Only random numbers
- D
Only blockchain data
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✓ A. Price feeds, weather data, sports scores, etc.
120
What is the oracle problem?
- A
The challenge of ensuring data from off-chain sources is reliable and secure
- B
The problem of slow oracles
- C
The problem of expensive oracles
- D
The problem of centralized oracles
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✓ A. The challenge of ensuring data from off-chain sources is reliable and secure
❓Frequently Asked Questions
What is Blockchain?
Blockchain is a decentralized, distributed digital ledger that records transactions across many computers so that the record cannot be altered retroactively without the alteration of all subsequent blocks.
Why should I practice Blockchain MCQs?
Practicing Blockchain MCQs helps prepare for interviews, competitive exams, and placement tests. It strengthens your understanding of blockchain fundamentals, cryptocurrencies, smart contracts, and distributed systems.
What are the key topics in Blockchain?
Key topics include Blockchain Basics, Bitcoin, Ethereum, Smart Contracts, Consensus Mechanisms, Wallets, Mining, Forks, Security, Decentralization, DeFi, NFTs, and more.
How can I prepare for Blockchain interviews?
Start with the basics, practice MCQs, build small projects, understand consensus algorithms, study real-world applications, and follow the latest trends in the blockchain space.
Is Blockchain only about cryptocurrency?
No, blockchain has many applications beyond cryptocurrency, including supply chain, healthcare, voting, digital identity, and decentralized finance (DeFi).
What is the future of Blockchain technology?
Blockchain is expected to revolutionize many industries by providing transparent, secure, and decentralized solutions. With advancements in scalability and interoperability, blockchain will become more integrated into everyday systems.