Learn React Js MCQs
Prepare React Js MCQs (Multiple choice Questions) for exam and job interviews.
What is the purpose of `useImperativeHandle`?
1) To customize the instance value that is exposed to parent components when using `ref`
2) To manage state
3) To handle side effects
4) To create refs
Answer : Option 1
How do you handle asynchronous operations in a functional component?
1) By using `useEffect` and Promises
2) By using lifecycle methods
3) By using synchronous code
4) By using global variables
Answer : Option 1
What does `useDebugValue` do?
1) Displays a label in React DevTools for custom hooks
2) Manages state
3) Handles side effects
4) Creates refs
Answer : Option 1
How do you ensure a component updates correctly with new props?
1) By using `componentDidUpdate`
2) By using `componentWillMount`
3) By using global variables
4) By using refs
Answer : Option 1
What does the `strict` mode in React do?
1) Helps identify potential problems in an application
2) Optimizes performance
3) Handles state management
4) Creates refs
Answer : Option 1
How do you implement error boundaries in React?
1) By creating a class component with `componentDidCatch` and `getDerivedStateFromError`
2) By using functional components
3) By using hooks only
4) By using global error handlers
Answer : Option 1
What is the main purpose of `React.memo`?
1) To optimize functional components by memoizing them
2) To manage state
3) To create refs
4) To handle side effects
Answer : Option 1
How do you handle multiple selectors in a form?
1) By using controlled components and managing their state
2) By using uncontrolled components
3) By using global variables
4) By using refs
Answer : Option 1
What is the benefit of using `PropTypes`?
1) To validate the props passed to a component
2) To manage state
3) To handle side effects
4) To create refs
Answer : Option 1
How do you implement routing in React?
1) By using `React Router`
2) By using Redux
3) By using local state
4) By using props
Answer : Option 1