Solidity Concepts for Contract Development BDC Practice Questions (Page 2)

Questions 6–10

1. 6application · medium

   A contract has an admin role. The developer wants to create a function that only the admin can call to pause the contract. Which function signature and modifier combination is correct?

   • Afunction pause() public onlyAdmin { paused = true; }
   • Bfunction pause() internal onlyAdmin { paused = true; }
   • Cfunction pause() external onlyAdmin { paused = true; }
   • Dfunction pause() private onlyAdmin { paused = true; }
   Reveal Solution Discussion Select an answer first
2. 7foundation · easy

   In Solidity, which data type is used to represent a fixed-size unsigned integer of 256 bits?

   • Abytes32
   • Buint256
   • Cint256
   • Daddress
   Reveal Solution Discussion Select an answer first
4. 8foundation · easy

   Which Solidity feature is used to emit information that can be efficiently retrieved by off-chain applications?

   • AStructs
   • BEvents
   • CModifiers
   • DMappings
   Reveal Solution Discussion Select an answer first
5. 9foundation · easy

   Which Solidity data structure is a key-value store that does not allow iteration over its keys?

   • AStruct
   • BMapping
   • CArray
   • DEnum
   Reveal Solution Discussion Select an answer first
6. 10foundation · easy

   Which Solidity construct allows a contract to inherit functions and state variables from another contract?

   • Aabstract contract
   • Blibrary
   • Cis keyword
   • Dinterface
   Reveal Solution Discussion Select an answer first