Architectural and Protocol Innovations BDC Practice Questions (Page 7)

Questions 31–33

1. 31application · medium

   A blockchain platform is evaluating ways to improve transaction privacy without sacrificing the ability to audit the total supply of a token. Which protocol-level technique allows a user to prove that they have enough balance for a transaction without revealing the exact balance?

   • AStealth addresses
   • BHomomorphic encryption
   • CRange proofs
   • DRing signatures
   Reveal Solution Discussion Select an answer first
2. 32expert · hard

   A blockchain network is considering a move from proof-of-work (PoW) to proof-of-stake (PoS). The team is concerned about the 'nothing at stake' problem. Which mechanism is specifically designed to penalize validators who validate blocks on multiple forks?

   • AA checkpoint mechanism that finalizes blocks periodically
   • BA longer block time to reduce the chance of forks
   • CA higher block reward to incentivize honest behavior
   • DSlashing conditions that forfeit a validator's stake if they sign conflicting blocks
   Reveal Solution Discussion Select an answer first
3. 33expert · hard

   A developer is designing a layer-2 solution that uses optimistic rollups. They need to ensure that users can withdraw funds from the rollup to the main chain. What is the minimum requirement for a user to withdraw funds if the rollup operator is malicious?

   • AThe user must obtain a signature from the rollup operator
   • BThe user must provide a zero-knowledge proof of their balance to the main chain
   • CThe user must wait for the next main-chain block to be mined
   • DThe user must submit a withdrawal request and wait for the challenge period to expire without a successful fraud proof
   Reveal Solution Discussion Select an answer first