Blockchain Consensus Mechanisms and Their Applications BBLC Practice Questions (Page 6)

Questions 26–30

1. 26foundation · easy

   Why is consensus essential for a distributed ledger?

   • AIt eliminates the need for cryptographic hashing
   • BIt encrypts all data stored on the blockchain
   • CIt prevents double-spending and ensures all nodes have the same transaction history
   • DIt allows a single node to control the entire network
   Reveal Solution Discussion Select an answer first
2. 27foundation · easy

   What is the core approach of Practical Byzantine Fault Tolerance (PBFT)?

   • AState machine replication where nodes agree on the order of operations through multiple rounds of voting
   • BRandom selection of a leader based on stake
   • CCompetitive puzzle solving to determine who can add the next block
   • DA single primary node that dictates all decisions to other nodes
   Reveal Solution Discussion Select an answer first
4. 28foundation · easy

   In a DeFi application, why might Proof of Stake be preferred over Proof of Work?

   • ATo eliminate the need for a native token
   • BTo reduce transaction costs and increase scalability while maintaining security
   • CTo ensure that the network is completely anonymous
   • DTo allow anyone to mine without specialized hardware
   Reveal Solution Discussion Select an answer first
5. 29expert · hard

   A global payment network is designing a blockchain to process cross-border transactions. They have three main requirements: (1) high throughput to handle millions of transactions per day, (2) finality within seconds to prevent double-spending, and (3) a decentralized governance model where token holders can influence protocol upgrades. They are considering PoW, PoS, DPoS, and PBFT. Which mechanism best balances all three requirements?

   • AProof of Work (PoW)
   • BDelegated Proof of Stake (DPoS)
   • CPractical Byzantine Fault Tolerance (PBFT)
   • DProof of Stake (PoS)
   Reveal Solution Discussion Select an answer first
6. 30application · medium

   A small cryptocurrency mining operation has a limited number of GPUs and wants to earn a steady income from mining a PoW coin. The operator is concerned about the variance in reward distribution. What is the most effective strategy to address this concern?

   • AMine solo and rely on the law of large numbers over time
   • BSwitch to a PoS coin and stake the existing GPUs
   • CJoin a mining pool that combines hashing power and distributes rewards proportionally
   • DPurchase ASIC miners to increase individual hashing power
   Reveal Solution Discussion Select an answer first