Blockchain Developer FREE Blockchain Developer Blockchain Fundamentals and Cryptography Questions and Answers 2

Question 1

What is the primary purpose of a Merkle tree in blockchain technology?

Accepted Answer

To efficiently verify the integrity of large datasets

Answer

To encrypt transaction data for privacy

Answer

To determine the order of block creation

Answer

To manage peer-to-peer network connections

Question 2

Which cryptographic property ensures that even a single-bit change in input produces a completely different hash output?

Accepted Answer

Avalanche effect

Answer

Collision resistance

Answer

Preimage resistance

Answer

Determinism

Question 3

In a proof-of-work consensus mechanism, what does the nonce value represent?

Accepted Answer

A variable miners adjust to find a valid block hash

Answer

The block reward amount

Answer

The timestamp of the block

Answer

The number of transactions in a block

Question 4

What type of cryptography does Bitcoin use for generating wallet addresses and signing transactions?

Accepted Answer

Elliptic Curve Digital Signature Algorithm (ECDSA)

Answer

RSA asymmetric encryption

Answer

Advanced Encryption Standard (AES)

Answer

Diffie-Hellman key exchange

Question 5

What is a 51% attack in blockchain?

Accepted Answer

When a single entity controls the majority of mining power and can manipulate the chain

Answer

When 51% of nodes go offline simultaneously

Answer

When more than half of all tokens are held by one wallet

Answer

When a smart contract contains a critical vulnerability

Question 6

Which data structure links blocks together to form an immutable chain?

Accepted Answer

Each block containing the cryptographic hash of the previous block's header

Answer

Doubly linked list with timestamps

Answer

A centralized index table mapping block numbers to data

Answer

A directed acyclic graph with random connections