Keys are given to a list of elements in react. These keys should be -

ReactJS - Quiz(MCQ)

Unique in the DOM

Do not requires to be unique

Unique among the siblings only

All of the above

Correct Answer : Unique among the siblings only

Recent Updates in React.JS

Q .

What do you need to change about this code to get it to run?

class clock extends React.Component {
  render() {
    return <h1>Look at the time: {this.props.time}</h1>;
  }
}

Remove this

Capitalize clock

Remove the render method

Add quotes around the return value

Correct Answer : Capitalize clock

Q .

Which Hook could be used to update the document's title?

useEffect(function updateTitle() { document.title = name + ' ' + lastname; });

useEffect(() => { title = name + ' ' + lastname; });

useEffect(function updateTitle() { name + ' ' + lastname; });

useEffect(function updateTitle() { title = name + ' ' + lastname; });

Correct Answer :

useEffect(function updateTitle() { document.title = name + ' ' + lastname; });