Deploy and Manage dApps BDC Practice Questions (Page 2)

Questions 6–10

1. 6foundation · easy

   What is the purpose of using a local blockchain network (e.g., Ganache or Hardhat Network) during dApp development?

   • ATo increase the security of the deployed contract
   • BTo permanently store the dApp's production data
   • CTo simulate the mainnet environment for testing without spending real funds
   • DTo replace the need for a backend server
   Reveal Solution Discussion Select an answer first
2. 7foundation · easy

   Why is versioning important for smart contract deployments?

   • ATo track changes and enable rollback to a previous implementation if needed
   • BTo increase the gas efficiency of the contract
   • CTo allow multiple contracts to share the same address
   • DTo automatically fix security vulnerabilities without user action
   Reveal Solution Discussion Select an answer first
4. 8expert · hard

   A dApp's smart contract function sometimes reverts, but only when called by certain users. The revert reason is not shown in the frontend. The developer suspects a logic error related to user-specific data. Which debugging approach would be most efficient?

   • AUse a local fork of the mainnet and replay the failed transaction with the specific user's state.
   • BIncrease the gas limit for all transactions from the affected users.
   • CAdd a try-catch block in the frontend to catch the revert and display it.
   • DAsk the affected users to clear their browser cache and retry.
   Reveal Solution Discussion Select an answer first
5. 9foundation · easy

   What is the primary purpose of monitoring a dApp's smart contract events?

   • ATo track important state changes and user actions in real time
   • BTo modify the contract's logic dynamically
   • CTo store large amounts of data off-chain
   • DTo increase the transaction throughput of the network
   Reveal Solution Discussion Select an answer first
6. 10application · medium

   A dApp's backend frequently queries a smart contract for the same data, causing high latency. The data changes only when a specific event is emitted. What is the best way to reduce latency?

   • AUse a WebSocket subscription to listen for the event and cache the data locally.
   • BIncrease the gas limit for the queries to speed them up.
   • CMove the data to a centralized database and update it manually.
   • DUse a REST API to poll the contract every few seconds.
   Reveal Solution Discussion Select an answer first