Data and Transaction Flow in Blockchain BDC Practice Questions (Page 3)

Questions 11–15

1. 11application · medium

   A miner on a Proof-of-Work blockchain is assembling a new block. The mempool contains thousands of transactions. Which transactions will the miner include in the block?

   • AThe transactions that were received first, regardless of their fees.
   • BThe transactions with the highest fees, up to the block's gas limit.
   • CA random selection of transactions from the mempool to ensure fairness.
   • DAll transactions in the mempool, regardless of the block size limit.
   Reveal Solution Discussion Select an answer first
2. 12expert · hard

   A node operator notices that a valid transaction is not being propagated to the network. The transaction was broadcast by a peer, but the node is not relaying it. Which configuration setting is most likely causing this issue?

   • AThe node's signature verification is disabled, so it rejects the transaction.
   • BThe node's mempool is full, so it drops the transaction instead of relaying it.
   • CThe node's block size limit is too small, so it cannot include the transaction.
   • DThe node's peer list is empty, so it cannot relay the transaction.
   Reveal Solution Discussion Select an answer first
4. 13application · medium

   A node on a blockchain network receives a new block from a peer. Before accepting it, the node must verify that the block's previous hash matches the hash of the last block in its local chain. What is this process called?

   • AConsensus finality
   • BTransaction propagation
   • CMempool management
   • DBlock validation
   Reveal Solution Discussion Select an answer first
5. 14application · easy

   A user sends a transaction to a blockchain network. The transaction is validated, propagated, included in a block, and the block is added to the chain. Which step in the transaction lifecycle occurs last?

   • AThe transaction is added to the mempool of each node
   • BThe transaction receives sufficient confirmations to be considered final
   • CThe transaction is included in a block
   • DThe transaction is broadcast to all nodes
   Reveal Solution Discussion Select an answer first
6. 15foundation · easy

   What is the role of a node when it receives a new transaction during propagation?

   • AValidate the transaction and forward it to its peers if valid
   • BDiscard the transaction if it is not from a trusted source
   • CEncrypt the transaction and send it to the network's central coordinator
   • DImmediately add it to the next block without validation
   Reveal Solution Discussion Select an answer first