Blockchain Developer FREE Blockchain Developer Token Standards and NFTs Questions and Answers 2

Question 1

Which ERC standard introduced the concept of semi-fungible tokens by combining fungible and non-fungible token functionality in a single contract?

Accepted Answer

ERC-1155

Answer

ERC-721

Answer

ERC-20

Answer

ERC-777

Question 2

What function in the ERC-721 standard is used to safely transfer an NFT while ensuring the recipient contract can handle it?

Accepted Answer

safeTransferFrom

Answer

transferFrom

Answer

approve

Answer

send

Question 3

In ERC-20, what happens if a user calls transfer() with an amount exceeding their balance?

Accepted Answer

The transaction reverts

Answer

The transfer sends the maximum available balance

Answer

A partial transfer occurs

Answer

The recipient receives zero tokens

Question 4

What is the primary purpose of the tokenURI function in ERC-721?

Accepted Answer

To return a URI pointing to the token's metadata

Answer

To generate the token's unique identifier

Answer

To verify token ownership

Answer

To set the token's sale price

Question 5

Which vulnerability can occur when an ERC-20 token's approve function is called to change an existing allowance without first setting it to zero?

Accepted Answer

Front-running double-spend attack

Answer

Reentrancy attack

Answer

Integer overflow

Answer

Denial of service

Question 6

What does the ERC-2981 standard define for NFTs?

Accepted Answer

A standardized royalty payment interface

Answer

A new token minting mechanism

Answer

A cross-chain bridge protocol

Answer

A metadata encryption scheme