In Solidity, which of the following is the recommended way to enforce that only the contract owner can call a specific function?

Rely on the function being private

Use a modifier that checks msg.sender against the owner address

Use a require statement that compares block.coinbase to the owner

Check tx.origin for the owner address

A team is preparing to audit a smart contract that handles token transfers. They want to identify potential integer overflow issues and logic errors before deployment. Which approach provides the most comprehensive automated analysis?

Write unit tests that cover all functions with expected inputs.

Run a static analysis tool like Slither to detect common vulnerabilities.

Deploy the contract on a testnet and manually test with random inputs.

Use a code formatter to ensure consistent style.

A smart contract developer is asked to create a contract that automatically pays out insurance claims based on weather data from an oracle. The contract is intended to be immutable. However, the oracle data source might change over time. Which design consideration is most important?

Rely on the oracle to be available forever.

Keep the contract fully immutable, including the oracle address.

Use multiple oracles to reduce the risk of a single point of failure.

Include an upgrade mechanism for the oracle address.

A dApp team is integrating a third-party KYC provider to verify user identities. They want to ensure that the KYC data is not exposed on the blockchain. Which design pattern best achieves this?

Store the full KYC data on-chain for transparency.

Store KYC verification results on-chain as a boolean flag, with raw data kept off-chain.

Encrypt the KYC data and store it on-chain.

Use a centralized database and do not interact with the blockchain.

When integrating user privacy into dApp development, which practice is most aligned with data protection principles?

Using the same address for all user interactions to simplify tracking

Storing all user data on-chain for transparency

Sharing user data with third parties without consent

Collecting only the minimum personal data necessary for the functionality

EC-CouncilBlockchain Business Leader Certification

Domain 4Objective 6

Security and Compliance in Smart Contracts BBLC Practice Questions (Page 5)

Part of the Ethereum, Smart Contracts, and dApps domain, which makes up ~14% of our current practice bank.

43questions here

9free pages

6concepts

Questions 21–25

21foundation · easy
In Solidity, which of the following is the recommended way to enforce that only the contract owner can call a specific function?
Select an answer first
22application · medium
A team is preparing to audit a smart contract that handles token transfers. They want to identify potential integer overflow issues and logic errors before deployment. Which approach provides the most comprehensive automated analysis?
Select an answer first
23expert · hard
A smart contract developer is asked to create a contract that automatically pays out insurance claims based on weather data from an oracle. The contract is intended to be immutable. However, the oracle data source might change over time. Which design consideration is most important?
Select an answer first
24application · medium
A dApp team is integrating a third-party KYC provider to verify user identities. They want to ensure that the KYC data is not exposed on the blockchain. Which design pattern best achieves this?
Select an answer first
25foundation · easy
When integrating user privacy into dApp development, which practice is most aligned with data protection principles?
Select an answer first

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