Smart Contract Requirements and Architecture BBLC Practice Questions (Page 7)

Questions 31–35

1. 31expert · hard

   A team has developed a complex DeFi contract with multiple interacting functions. They want to ensure that the contract is free from reentrancy vulnerabilities and that all state changes are correct. Which testing and validation approach is most appropriate?

   • ADeploy to mainnet and monitor for anomalies.
   • BPerform a combination of unit tests, integration tests, and formal verification.
   • CUse formal verification to mathematically prove the contract's properties.
   • DRun unit tests on each function individually.
   Reveal Solution Discussion Select an answer first
2. 32foundation · easy

   In a smart contract that manages a decentralized voting system, which access-control mechanism would best allow only registered voters to cast a vote?

   • AA modifier that checks if the caller is in a mapping of registered voters
   • BA function that is only callable by the contract owner
   • CA require statement that checks the block timestamp
   • DA public function that anyone can call
   Reveal Solution Discussion Select an answer first
4. 33application · medium

   A company is building a loyalty-points smart contract. The business team states that points should expire after 12 months, and the IT team wants to minimize storage costs. Which requirement should be documented as a functional requirement?

   • AOnly authorized administrators can adjust point balances.
   • BThe contract must be able to handle a high volume of point redemptions without excessive gas costs.
   • CThe system should be available 99.9% of the time.
   • DPoints that are not used within 12 months must be automatically removed from the user's balance.
   Reveal Solution Discussion Select an answer first
5. 34foundation · easy

   Which upgradeability pattern allows a smart contract to delegate calls to a separate logic contract while keeping the state in a proxy contract?

   • AThe observer pattern
   • BThe proxy pattern
   • CThe factory pattern
   • DThe singleton pattern
   Reveal Solution Discussion Select an answer first
6. 35foundation · easy

   What is a primary reason to use an upgradeability pattern in a smart contract?

   • ATo make the contract immutable
   • BTo increase the block gas limit
   • CTo allow fixing bugs in the contract logic after deployment
   • DTo reduce the cost of deployment
   Reveal Solution Discussion Select an answer first