Blockchain Technology Concepts and Distributed Ledger Technology (DLT) BDC Practice Questions (Page 4)

Questions 16–20

1. 16application · medium

   An insurance company wants to automate claim payouts when a flight is delayed more than two hours. They plan to use a smart contract on a blockchain. What is the primary benefit of using a smart contract for this process?

   • AThe contract creates a private database that only the insurance company can modify.
   • BThe contract automatically executes the payout when the delay condition is met, without requiring manual claims processing.
   • CThe contract replaces the need for any external data source because it can access flight data directly from the airline's internal system.
   • DThe contract stores the insurance policy in an encrypted format that only the policyholder can read.
   Reveal Solution Discussion Select an answer first
2. 17application · medium

   A group of NGOs wants to create a donation-tracking system where donors can verify that their funds were used as intended. They want to eliminate the need for a single auditing firm to be trusted. Which approach best achieves this goal?

   • APublish all transactions on a public website with a digital signature from the auditing firm
   • BDeploy a permissioned blockchain where all NGOs and a few independent auditors run nodes and validate transactions
   • CUse a consortium blockchain where only the lead NGO can validate transactions
   • DUse a centralized database with an immutable audit log maintained by the lead NGO
   Reveal Solution Discussion Select an answer first
4. 18application · medium

   A developer is designing a blockchain-based document notarization service. A user claims that a document was notarized on a certain date, but the user has lost the original transaction ID. How can the service prove the document was notarized without relying on the user's memory?

   • ABy hashing the document and searching the blockchain for a transaction that contains that hash.
   • BBy looking up the user's account balance to see if a transaction fee was paid on that date.
   • CBy asking the user to provide the private key used to sign the transaction.
   • DBy checking the user's email for the confirmation message sent by the service.
   Reveal Solution Discussion Select an answer first
5. 19application · medium

   A developer is building a blockchain-based voting system. They want to ensure that once a vote is cast, it cannot be changed without detection. Which use of cryptographic hashing directly supports this requirement?

   • AStoring the hash of each vote in a Merkle tree and including the root in the block header.
   • BEncrypting each vote with the voter's public key so only the voter can read it.
   • CUsing a random number generator to create a unique ID for each vote.
   • DHashing the voter's identity and storing it in a separate database.
   Reveal Solution Discussion Select an answer first
6. 20foundation · easy

   How does decentralization in a blockchain establish trust among participants?

   • ABy encrypting all data so that only the network owner can read it.
   • BBy having a trusted third party verify every transaction.
   • CBy allowing participants to verify transactions independently using the shared ledger.
   • DBy requiring all participants to sign a legal contract before joining.
   Reveal Solution Discussion Select an answer first