Bitcoin Blockchain Architecture and Network Transactions BFC Practice Questions (Page 11)

Questions 51–54

1. 51foundation · easy

   In the Bitcoin UTXO model, what does an Unspent Transaction Output (UTXO) represent?

   • AA block that has not yet been mined
   • BA record of all transactions ever made by a user
   • CA specific amount of bitcoin that can be used as input to a new transaction
   • DA private key associated with a bitcoin address
   Reveal Solution Discussion Select an answer first
2. 52application · medium

   A developer is writing a custom Bitcoin transaction and needs to create an output that can only be spent by someone who can provide a specific digital signature. Which script type should they use?

   • AOP_RETURN script
   • BP2SH (Pay-to-Script-Hash) script
   • CP2PKH (Pay-to-Public-Key-Hash) script
   • DMultisig script requiring 2-of-3 signatures
   Reveal Solution Discussion Select an answer first
4. 53expert · hard

   A Bitcoin exchange is planning to support a new soft fork that introduces a new transaction type. The exchange runs full nodes. What is the most important consideration before activating the new feature?

   • ADo nothing because soft forks are backward-compatible and require no action.
   • BWait for the majority of miners to upgrade before the exchange upgrades.
   • CEnsure all exchange nodes are upgraded to the new client to avoid accepting invalid blocks.
   • DUpgrade only the wallet software, not the full nodes.
   Reveal Solution Discussion Select an answer first
5. 54foundation · easy

   In Bitcoin's proof-of-work consensus, what does a miner need to find to create a new block?

   • AA digital signature from the previous block's miner
   • BA nonce that, when hashed with the block header, produces a hash below a target difficulty
   • CA timestamp that is exactly 10 minutes after the previous block
   • DA private key that matches the block's public key
   Reveal Solution Discussion Select an answer first