Learn React Js MCQs
Prepare React Js MCQs (Multiple choice Questions) for exam and job interviews.
How do you create a context in React?
1) Using `useState`
2) Using `React.createContext`
3) Using `useRef`
4) Using `useReducer`
Answer : Option 2
What is the purpose of the `useTransition` hook?
1) To create refs
2) To manage state
3) To defer rendering a non-urgent update
4) To handle side effects
Answer : Option 3
How do you handle user inputs in React?
1) Using `useRef`
2) Using `controlled components`
3) Using `useEffect`
4) Using `useState`
Answer : Option 2
What is the purpose of `useDeferredValue`?
1) To handle side effects
2) To defer updating a value until after a higher priority update
3) To create a new context
4) To optimize performance
Answer : Option 2
How do you handle errors in React components?
1) Using `try-catch` in `render`
2) Using `Error Boundaries`
3) Using `useState`
4) Using `useEffect`
Answer : Option 2
What is the purpose of the `useMemo` hook in React?
1) To manage state
2) To optimize rendering by memoizing a value
3) To handle side effects
4) To create refs
Answer : Option 2
How do you pass data between siblings in React?
1) Using `props`
2) Using `context`
3) Using a parent component
4) Using `useState`
Answer : Option 3
What is the purpose of `React.StrictMode`?
1) To manage state
2) To optimize performance
3) To identify potential problems in the application
4) To handle side effects
Answer : Option 3
How do you handle conditional rendering in React?
1) Using `useState`
2) Using `useEffect`
3) Using `if-else` or ternary operators
4) Using `useContext`
Answer : Option 3
What is the purpose of `useRef` in React?
1) To create a mutable object that persists across renders
2) To manage state
3) To handle side effects
4) To optimize rendering
Answer : Option 1