Blockchain Ecosystem and Use Cases BDC Practice Questions (Page 9)

Questions 41–45

1. 41expert · hard

   A blockchain network uses a delegated proof-of-stake (DPoS) consensus mechanism where token holders vote for a small set of block producers. The network is facing criticism that the block producers are becoming too centralized and are colluding to censor transactions. What is the most effective governance change to address this issue?

   • AAllow block producers to serve indefinitely without re-election
   • BIncrease the number of block producers and implement random selection from a larger pool
   • CRemove the voting mechanism and let the core developers choose block producers
   • DRequire block producers to stake a larger amount of tokens
   Reveal Solution Discussion Select an answer first
2. 42foundation · easy

   What is a common compliance issue when using a public blockchain for storing personal data?

   • AThe blockchain cannot store large files
   • BThe immutability of the ledger conflicts with data erasure requirements
   • CThe blockchain does not support encryption
   • DThe blockchain is too fast for regulators to monitor
   Reveal Solution Discussion Select an answer first
4. 43application · medium

   A pharmaceutical company wants to use blockchain to track the temperature of vaccines from manufacturing to delivery. They need to share data with regulators and hospitals, but they are concerned about exposing proprietary supply chain details. Which approach best balances transparency and confidentiality?

   • AUse a private blockchain with no external access, and provide regulators with periodic reports.
   • BUse a public blockchain and rely on encryption of all shipment data.
   • CUse a permissioned blockchain where only authorized participants can view the temperature data and shipment details.
   • DStore all data off-chain and only share it with regulators upon request.
   Reveal Solution Discussion Select an answer first
5. 44expert · hard

   A developer is writing a smart contract for a decentralized lending platform. The contract must handle collateral in multiple cryptocurrencies and automatically liquidate positions when the collateral value falls below a threshold. Which design consideration is most critical to prevent exploitation?

   • ARely on the blockchain's native consensus to determine collateral values.
   • BAllow the contract owner to manually adjust collateral thresholds.
   • CUse a price oracle that aggregates data from multiple sources to prevent price manipulation.
   • DUse a fixed collateral ratio for all cryptocurrencies.
   Reveal Solution Discussion Select an answer first
6. 45foundation · easy

   How does a dApp leverage blockchain technology to ensure transparency of its operations?

   • AIt stores all data on the user's device
   • BIt encrypts all data so only the dApp owner can view it
   • CIt uses a private database that only the developer can access
   • DAll transactions and state changes are recorded on a public ledger
   Reveal Solution Discussion Select an answer first