Blockchain and it's Applications

1. What is a blockchain?

• A type of computer virus

• A centralized database

• A distributed and immutable ledger

• A cryptocurrency wallet

Which of the following is the most well-known application of blockchain technology?

• Cloud computing

• Internet of Things

• Bitcoin

• Email

In blockchain, what is the purpose of a nonce?

• To store user information

• To identify a miner

• To vary the hash result during mining

• To reduce network latency

What does a smart contract do?

• Automatically executes terms of an agreement

• Repairs blocks in a chain

• Encrypts emails

• Monitors social media

Which consensus mechanism is used by Bitcoin?

• Practical Byzantine Fault Tolerance (PBFT)

• Proof of Work (PoW)

• Delegated Proof of Stake (DPoS)

• Proof of Stake (PoS)

What is a “block” in blockchain?

• A cryptocurrency unit

• A virus that attacks miners

• A security vulnerability

• A group of transactions bundled together

Which language is commonly used to write smart contracts on Ethereum?

• Python

• Rust

• Golang

• Solidity

What is meant by “decentralization” in blockchain?

• Data is distributed across multiple nodes

• Stored on a local computer only

• Controlled by one central authority

• Offline network

Which of the following is NOT a feature of blockchain?

• Centralized control

• Immutability

• Transparency

• Security

What is a “hash” in the context of blockchain?

• A digital signature

• A transaction fee

• An output of a cryptographic function representing data

• A method of encryption