CBCP Blockchain Fundamental 2

Question 1

Which property of a blockchain ensures that once a block is added, its data cannot be altered without invalidating all subsequent blocks?

Accepted Answer

Immutability

Answer

Immutability means that altering any block's data changes its hash, breaking the chain link to every block that follows.

Question 2

In the context of blockchain, what does the term 'fork' refer to?

Accepted Answer

A change in the blockchain protocol that creates two diverging chains

Answer

A fork occurs when a change in protocol rules causes nodes to split, potentially following two different versions of the chain.

Question 3

What distinguishes a 'hard fork' from a 'soft fork' in blockchain protocol upgrades?

Accepted Answer

Hard forks are backward-incompatible; soft forks are backward-compatible

Answer

A hard fork introduces rules incompatible with the old protocol, while a soft fork's new rules still accept old-format blocks.

Question 4

Which component of a block header links it cryptographically to the previous block?

Accepted Answer

Previous block hash

Answer

The previous block hash stored in each block header creates the cryptographic chain that makes tampering detectable.

Question 5

In blockchain terminology, what is a 'genesis block'?

Accepted Answer

The very first block in a blockchain

Answer

The genesis block is block zero — the hardcoded first block that has no predecessor and anchors the entire chain.

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